<PAGE> PAGE 1
000 A000000 12/31/1999
000 C000000 0000354603
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 U
001 A000000 SEI LIQUID ASSET TRUST
001 B000000 811-3231
001 C000000 8003425734
002 A000000 2 OLIVER STREET
002 B000000 BOSTON
002 C000000 MA
002 D010000 02109
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 Y
007 B000000 3
007 C010100 1
007 C020100 TREASURY SECURITIES FUND
007 C030100 N
007 C010200 2
007 C020200 GOVERNMENT SECURITIES FUND
007 C030200 N
007 C010300 3
007 C010400 4
007 C020400 PRIME OBLIGATION FUND
007 C030400 N
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
010 A00AA01 SEI FUND RESOURCES
010 C01AA01 WAYNE
010 C02AA01 PA
010 C03AA01 19087
022 A000001 LEHMAN BROTHERS
022 B000001 13-2927667
022 C000001 6261695
022 D000001 0
022 A000002 LUMMIS & COMPANY
022 B000002 04-3200030
022 C000002 3685706
022 D000002 354100
022 A000003 GOLDMAN SACHS
<PAGE> PAGE 2
022 B000003 13-5108880
022 C000003 1340985
022 D000003 948062
022 A000004 ABN AMRO
022 B000004 13-3227945
022 C000004 1057400
022 D000004 1022400
022 A000005 SUN BANK INC.
022 C000005 1584432
022 D000005 369021
022 A000006 J.P.MORGAN
022 B000006 13-3224016
022 C000006 1266045
022 D000006 675180
022 A000007 MORGAN STANLEY
022 B000007 13-2655998
022 C000007 1035003
022 D000007 736604
022 A000008 EURO BANKERS
022 B000008 12-3410896
022 C000008 1390362
022 D000008 0
022 A000009 MERRILL LYNCH
022 B000009 13-5674085
022 C000009 661263
022 D000009 0
022 A000010 BARCLAY DE ZOETE WEDD
022 B000010 13-4942190
022 C000010 326919
022 D000010 0
023 C000000 23199817
023 D000000 5295237
027 000000 Y
077 A000000 N
024 000100 Y
025 A000101 AB-AMRO
025 B000101 13-3227945
025 C000101 D
025 D000101 15000
025 A000102 BARCLAY DE ZOETE WEDD
025 B000102 13-4942190
025 C000102 D
025 D000102 70000
025 A000103 JP MORGAN AND COMPANY
025 B000103 13-3224016
025 C000103 D
025 D000103 75000
025 A000104 LEHMAN BROTHERS
025 B000104 13-2927667
025 C000104 D
025 D000104 52300
<PAGE> PAGE 3
025 A000105 PARIBAS CORPORATION
025 B000105 13-3235334
025 C000105 D
025 D000105 80000
025 A000106 WARBURG DILLON
025 B000106 13-2932966
025 C000106 D
025 D000106 55000
025 D000107 0
025 D000108 0
025 D000109 0
025 D000110 0
025 D000111 0
025 D000112 0
025 D000113 0
025 D000114 0
025 D000115 0
025 D000116 0
025 D000117 0
025 D000118 0
025 D000119 0
025 D000120 0
025 D000121 0
025 D000122 0
025 D000123 0
025 D000124 0
028 A010100 294161
028 A020100 57
028 A030100 0
028 A040100 313291
028 B010100 230469
028 B020100 63
028 B030100 0
028 B040100 243770
028 C010100 236231
028 C020100 67
028 C030100 0
028 C040100 234002
028 D010100 225541
028 D020100 66
028 D030100 0
028 D040100 220593
028 E010100 278011
028 E020100 67
028 E030100 0
028 E040100 271378
028 F010100 287495
028 F020100 78
028 F030100 0
028 F040100 322421
028 G010100 1551908
<PAGE> PAGE 4
028 G020100 398
028 G030100 0
028 G040100 1605455
028 H000100 0
062 A000100 Y
062 B000100 32.6
062 C000100 0.0
062 D000100 67.7
062 E000100 0.0
062 F000100 0.0
062 G000100 0.0
062 H000100 0.0
062 I000100 0.0
062 J000100 0.0
062 K000100 0.0
062 L000100 -0.3
062 M000100 0.0
062 N000100 0.0
062 O000100 0.0
062 P000100 0.0
062 Q000100 0.0
062 R000100 0.0
063 A000100 48
063 B000100 0.0
064 A000100 N
071 A000100 0
071 B000100 0
071 C000100 0
071 D000100 0
072 A000100 6
072 B000100 13931
072 C000100 0
072 D000100 0
072 E000100 0
072 F000100 90
072 G000100 1139
072 H000100 0
072 I000100 678
072 J000100 14
072 K000100 0
072 L000100 16
072 M000100 2
072 N000100 0
072 O000100 0
072 P000100 0
072 Q000100 0
072 R000100 3
072 S000100 9
072 T000100 1
072 U000100 0
072 V000100 0
<PAGE> PAGE 5
072 W000100 41
072 X000100 1993
072 Y000100 800
072 Z000100 12738
072AA000100 0
072BB000100 0
072CC010100 0
072CC020100 0
072DD010100 12792
072DD020100 5
072EE000100 0
073 A010100 0.0200
073 A020100 0.0200
073 B000100 0.0000
073 C000100 0.0000
074 A000100 97
074 B000100 347300
074 C000100 167129
074 D000100 0
074 E000100 0
074 F000100 0
074 G000100 0
074 H000100 0
074 I000100 0
074 J000100 0
074 K000100 0
074 L000100 749
074 M000100 12
074 N000100 515287
074 O000100 0
074 P000100 0
074 Q000100 0
074 R010100 0
074 R020100 0
074 R030100 0
074 R040100 2366
074 S000100 0
074 T000100 512921
074 U010100 512737
074 U020100 227
074 V010100 1.00
074 V020100 1.00
074 W000100 0.9997
074 X000100 46
074 Y000100 0
075 A000100 537843
075 B000100 0
076 000100 0.00
025 A000201 JP MORGAN
025 B000201 13-3224016
025 C000201 D
<PAGE> PAGE 6
025 D000201 1600
028 A010200 60267
028 A020200 40
028 A030200 0
028 A040200 74504
028 B010200 46338
028 B020200 55
028 B030200 0
028 B040200 39984
028 C010200 25874
028 C020200 52
028 C030200 0
028 C040200 32053
028 D010200 26344
028 D020200 62
028 D030200 0
028 D040200 16805
028 E010200 27893
028 E020200 68
028 E030200 0
028 E040200 53457
028 F010200 49355
028 F020200 34
028 F030200 0
028 F040200 57911
028 G010200 236071
028 G020200 311
028 G030200 0
028 G040200 274714
028 H000200 0
062 A000200 Y
062 B000200 0.0
062 C000200 97.7
062 D000200 2.3
062 E000200 0.0
062 F000200 0.0
062 G000200 0.0
062 H000200 0.0
062 I000200 0.0
062 J000200 0.0
062 K000200 0.0
062 L000200 0.0
062 M000200 0.0
062 N000200 0.0
062 O000200 0.0
062 P000200 0.0
062 Q000200 0.0
062 R000200 0.0
063 A000200 59
063 B000200 0.0
064 A000200 N
<PAGE> PAGE 7
071 A000200 0
071 B000200 0
071 C000200 0
071 D000200 0
072 A000200 6
072 B000200 2423
072 C000200 0
072 D000200 0
072 E000200 0
072 F000200 15
072 G000200 193
072 H000200 0
072 I000200 114
072 J000200 1
072 K000200 0
072 L000200 2
072 M000200 1
072 N000200 0
072 O000200 0
072 P000200 0
072 Q000200 0
072 R000200 0
072 S000200 1
072 T000200 0
072 U000200 0
072 V000200 0
072 W000200 5
072 X000200 332
072 Y000200 131
072 Z000200 2222
072AA000200 1
072BB000200 0
072CC010200 0
072CC020200 0
072DD010200 2220
072DD020200 0
072EE000200 0
073 A010200 0.0200
073 A020200 0.0000
073 B000200 0.0000
073 C000200 0.0000
074 A000200 8
074 B000200 1600
074 C000200 68503
074 D000200 0
074 E000200 0
074 F000200 0
074 G000200 0
074 H000200 0
074 I000200 0
074 J000200 0
<PAGE> PAGE 8
074 K000200 0
074 L000200 403
074 M000200 4
074 N000200 70518
074 O000200 0
074 P000200 0
074 Q000200 0
074 R010200 0
074 R020200 0
074 R030200 0
074 R040200 379
074 S000200 0
074 T000200 70139
074 U010200 70138
074 U020200 0
074 V010200 1.00
074 V020200 0.00
074 W000200 0.9997
074 X000200 23
074 Y000200 0
075 A000200 90850
075 B000200 0
076 000200 0.00
024 000400 N
025 A000401 CREDIT SUISSE FIRST BOSTON
025 B000401 13-3224016
025 C000401 D
025 D000401 15000
025 D000402 0
025 D000403 0
025 D000404 0
025 D000405 0
025 D000406 0
025 D000407 0
025 D000408 0
028 A010400 975430
028 A020400 2179
028 A030400 0
028 A040400 872077
028 B010400 809247
028 B020400 2458
028 B030400 0
028 B040400 877153
028 C010400 815836
028 C020400 2653
028 C030400 0
028 C040400 744028
028 D010400 840851
028 D020400 2736
028 D030400 0
028 D040400 789312
<PAGE> PAGE 9
028 E010400 729088
028 E020400 3207
028 E030400 0
028 E040400 700497
028 F010400 1067594
028 F020400 3449
028 F030400 0
028 F040400 964889
028 G010400 5238046
028 G020400 16682
028 G030400 0
028 G040400 4947956
028 H000400 0
062 A000400 Y
062 B000400 0.0
062 C000400 0.3
062 D000400 0.9
062 E000400 0.0
062 F000400 18.1
062 G000400 0.0
062 H000400 0.0
062 I000400 48.0
062 J000400 8.9
062 K000400 0.0
062 L000400 23.8
062 M000400 0.0
062 N000400 0.0
062 O000400 0.0
062 P000400 0.0
062 Q000400 0.0
062 R000400 0.0
063 A000400 46
063 B000400 0.0
064 A000400 N
071 A000400 0
071 B000400 0
071 C000400 0
071 D000400 0
072 A000400 6
072 B000400 40220
072 C000400 0
072 D000400 0
072 E000400 0
072 F000400 243
072 G000400 3073
072 H000400 0
072 I000400 1831
072 J000400 35
072 K000400 0
072 L000400 33
072 M000400 5
<PAGE> PAGE 10
072 N000400 0
072 O000400 0
072 P000400 0
072 Q000400 0
072 R000400 6
072 S000400 23
072 T000400 0
072 U000400 0
072 V000400 0
072 W000400 69
072 X000400 5318
072 Y000400 2095
072 Z000400 36997
072AA000400 0
072BB000400 0
072CC010400 0
072CC020400 0
072DD010400 37013
072DD020400 0
072EE000400 0
073 A010400 0.0300
073 A020400 0.0000
073 B000400 0.0000
073 C000400 0.0000
074 A000400 837
074 B000400 15000
074 C000400 1623380
074 D000400 0
074 E000400 0
074 F000400 0
074 G000400 0
074 H000400 0
074 I000400 0
074 J000400 0
074 K000400 0
074 L000400 10769
074 M000400 63
074 N000400 1650049
074 O000400 0
074 P000400 0
074 Q000400 0
074 R010400 0
074 R020400 0
074 R030400 0
074 R040400 7991
074 S000400 0
074 T000400 1642058
074 U010400 1642026
074 U020400 0
074 V010400 1.00
074 V020400 0.00
<PAGE> PAGE 11
074 W000400 0.9999
074 X000400 116
074 Y000400 0
075 A000400 1452934
075 B000400 0
076 000400 0.00
SIGNATURE MARK NAGLE
TITLE CONTROLLER
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000354603
<NAME> SEI LIQUID ASSET TRUST
<SERIES>
<NUMBER> 010
<NAME> TREASURY SECURITIES FUND CLASS A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 514429
<INVESTMENTS-AT-VALUE> 514429
<RECEIVABLES> 749
<ASSETS-OTHER> 109
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 515287
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 240
<TOTAL-LIABILITIES> 240
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 512964
<SHARES-COMMON-STOCK> 512737
<SHARES-COMMON-PRIOR> 565881
<ACCUMULATED-NII-CURRENT> 187
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (230)
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 515047
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 13931
<OTHER-INCOME> 0
<EXPENSES-NET> (1193)
<NET-INVESTMENT-INCOME> 12738
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 12738
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (12792)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1551904
<NUMBER-OF-SHARES-REDEEMED> (1605441)
<SHARES-REINVESTED> 393
<NET-CHANGE-IN-ASSETS> (53202)
<ACCUMULATED-NII-PRIOR> 246
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (230)
<GROSS-ADVISORY-FEES> 90
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1993
<AVERAGE-NET-ASSETS> 537843
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.02
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.02)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .44
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000354603
<NAME> SEI LIQUID ASSET TRUST
<SERIES>
<NUMBER> 011
<NAME> TREASURY SECURITIES FUND CLASS D
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 514429
<INVESTMENTS-AT-VALUE> 514429
<RECEIVABLES> 749
<ASSETS-OTHER> 109
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 515287
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 240
<TOTAL-LIABILITIES> 240
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 512964
<SHARES-COMMON-STOCK> 227
<SHARES-COMMON-PRIOR> 232
<ACCUMULATED-NII-CURRENT> 187
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (230)
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 515047
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 13931
<OTHER-INCOME> 0
<EXPENSES-NET> (1193)
<NET-INVESTMENT-INCOME> 12738
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 12738
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (5)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 4
<NUMBER-OF-SHARES-REDEEMED> (14)
<SHARES-REINVESTED> 5
<NET-CHANGE-IN-ASSETS> (6)
<ACCUMULATED-NII-PRIOR> 246
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (230)
<GROSS-ADVISORY-FEES> 90
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1993
<AVERAGE-NET-ASSETS> 537843
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.02
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.02)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.79
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000354603
<NAME> SEI LIQUID ASSET TRUST
<SERIES>
<NUMBER> 020
<NAME> GOVERNMENT SECURITIES FUND
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 70103
<INVESTMENTS-AT-VALUE> 70103
<RECEIVABLES> 403
<ASSETS-OTHER> 12
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 70518
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 379
<TOTAL-LIABILITIES> 379
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 70138
<SHARES-COMMON-STOCK> 70138
<SHARES-COMMON-PRIOR> 108470
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (2)
<ACCUMULATED-NET-GAINS> 3
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 70139
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 2423
<OTHER-INCOME> 0
<EXPENSES-NET> (201)
<NET-INVESTMENT-INCOME> 2222
<REALIZED-GAINS-CURRENT> 1
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 2223
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (2220)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 236071
<NUMBER-OF-SHARES-REDEEMED> (274714)
<SHARES-REINVESTED> 311
<NET-CHANGE-IN-ASSETS> (38329)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2
<OVERDISTRIB-NII-PRIOR> (4)
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 15
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 332
<AVERAGE-NET-ASSETS> 90850
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.02
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.02)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .44
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000354603
<NAME> SEI LIQUID ASSET TRUST
<SERIES>
<NUMBER> 040
<NAME> PRIME OBLIGATIONS FUND
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JUN-30-2000
<PERIOD-START> JUL-01-1999
<PERIOD-END> DEC-31-1999
<INVESTMENTS-AT-COST> 1638380
<INVESTMENTS-AT-VALUE> 1638380
<RECEIVABLES> 10769
<ASSETS-OTHER> 900
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1650049
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 7991
<TOTAL-LIABILITIES> 7991
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1642026
<SHARES-COMMON-STOCK> 1642026
<SHARES-COMMON-PRIOR> 1335254
<ACCUMULATED-NII-CURRENT> 37
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (5)
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 1642058
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 40220
<OTHER-INCOME> 0
<EXPENSES-NET> (3223)
<NET-INVESTMENT-INCOME> 36997
<REALIZED-GAINS-CURRENT> 1
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 36998
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (37013)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 5238046
<NUMBER-OF-SHARES-REDEEMED> (4947956)
<SHARES-REINVESTED> 16682
<NET-CHANGE-IN-ASSETS> 306757
<ACCUMULATED-NII-PRIOR> 53
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (6)
<GROSS-ADVISORY-FEES> 243
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5318
<AVERAGE-NET-ASSETS> 1452934
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.03
<PER-SHARE-GAIN-APPREC> 0.00
<PER-SHARE-DIVIDEND> (0.03)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .44
</TABLE>