SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

_________

FORM 11-K

_________

FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS

AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

_________________________

[X] ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES

EXCHANGE ACT OF 1934

For the fiscal year ended              December 31, 1999            

OR

[ ] TRANSITION REPORT PURSUANT TO SECTION 15(d)OF THE SECURITIES

EXCHANGE ACT OF 1934

For the transition period from                       to                          

Commission file number     2-84723     

Schering-Plough Corporation

One Giralda Farms

P.O. Box 1000

Madison, New Jersey 07940

TABLE OF CONTENTS                                                               

Supplemental schedules not included herein are omitted due to the absence of conditions under which they are required.

Schering-Plough Employees' Savings Plan:

We have audited the accompanying statements of net assets available for benefits of Schering-Plough Employees' Savings Plan (the "Plan") as of December 31, 1999 and 1998, and the related statement of changes in net assets available for benefits for the year ended December 31, 1999. These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted in the United States of America. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, such financial statements present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 1999 and 1998, and the changes in net assets available for benefits for the year ended December 31, 1999, in conformity with accounting principles generally accepted in the United States of America.

Our audits were conducted for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedule of Assets Held for Investment Purposes is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. This schedule is the responsibility of the Plan's management. Such schedule has been subjected to the auditing procedures applied in our audit of the basic 1999 financial statements, and, in our opinion, is fairly stated in all material respects when considered in relation to the basic 1999 financial statements taken as a whole.

/s/ Deloitte & Touche LLP

Parsippany, New Jersey

June 15, 2000

($ in 000's)

See Notes to Financial Statements.

See Notes to Financial Statements.

The Schering-Plough Employees' Savings Plan ("Plan") is a defined contribution plan open to all United States employees of Schering-Plough Corporation ("Company") and its participating subsidiaries who have attained one year of service. A year of service for eligibility purposes shall mean a twelve-month period, beginning with the day of the year the employee commenced employment. There were approximately 11,500 participants in the Plan at December 31, 1999 and 10,700 at December 31, 1998 .

Basis of Accounting - The accounts of the Plan have been prepared on an accrual basis in accordance with generally accepted accounting principles.

The financial statements were prepared in accordance with the financial reporting requirements of the Employee Retirement Income Security Act of 1974 ("ERISA") as permitted by the Securities and Exchange Commission.

Investment Valuation and Income Recognition - The Plan's investments are stated at fair value. Shares of registered investment companies are valued at quoted market prices which represent the net asset value of shares held by the Plan at year-end.

The Schering-Plough Stock Fund is valued using the unit accounting method whereby a participant's account value is expressed in units of participation rather than number of shares of Schering-Plough common stock.

The closing stock prices of Schering-Plough Corporation at December 31, 1999 and December 31, 1998 were $42 3/8 and $55 1/4, respectively; the closing price on June 15, 2000 was $48.1875.

Purchases and sales of securities are recorded on a trade-date basis. Interest income is recorded on the accrual basis. Dividend income is recorded on the ex-dividend date. Dividends recorded in the Schering-Plough Stock Fund are reinvested in Schering-Plough common stock units.

Participant loans are valued at cost which approximates fair value.

Payment of Benefits - Benefit payments are recorded when paid.

($ in 000's except per share amounts)

The following brief description of the Plan is provided for general information purposes only. Participants should refer to the Plan document for more complete information.

Salary Deferral Contributions - Each year participants may contribute from 1% to 4% (up to 10% for employees covered by a certain collective bargaining agreement) of pretax annual compensation, as defined in the Plan. Contributions are subject to certain limitations.

Participant Accounts - Each participant's account is credited with the participant's contribution and earnings thereon. Participants have a non-forfeitable right to their contributions plus (minus) actual earnings thereon which vest fully and immediately.

Investment Options - Upon enrollment in the Plan, a participant may direct their contributions into any of the following Vanguard Fiduciary Trust Company ("Vanguard") investment options:

Schering-Plough Stock Fund Fund is comprised of Schering-Plough common stock and a small percentage of cash as required for liquidity purposes. Participants may contribute up to a maximum investment election of 50% of their Salary Deferral Contribution into this fund.

Loan Fund - Participants may borrow from their fund accounts up to the lesser of one half of their account or $50 (reduced by any outstanding loans). Loan transactions are treated as a transfer between the investment funds and the Loan Fund. These loans bear a fixed rate of interest as determined to be reasonable by the Schering-Plough Employee Benefits Committee, and are repayable over periods not exceeding five years, except loans

Although it has not expressed any intent to do so, the Company has the right under the Plan to terminate the Plan subject to provisions of ERISA.

The Internal Revenue Service has issued a determination letter dated June 1, 1995 to the effect that the Plan is a qualified employee benefit plan, meeting the requirements of Section 401(a) of the Internal Revenue Code and the Trust established thereunder is exempt from Federal income taxes under Section 501(a). Accordingly, there is no provision for income taxes in the Plan's financial statements.

Contributions are held and managed by the Vanguard Group (the "Trustee"), which invests cash received, interest and dividend income and makes distributions to the participants. The Trustee also administers the payment of interest and principal on the participant loans.

($ in 000's except per share amounts)

Certain administrative functions are performed by officers or employees of the Company or its subsidiaries. No such officer or employee receives compensation from the Plan.

All plan administration expenses are borne by the Company.

($ in 000's except per share amounts)

8.   Fund Information

   The following funds represent 5% or more of the Plans net assets available for

   benefits at:

Effective January 1, 2000, the Plan was amended. Under the new terms, the one-year waiting period necessary to gain eligibility was discontinued. As such, employees hired on or after January 1, 2000, will be eligible as of their hire date. Employees hired between January 1, 1999 and December 31, 1999, became eligible as of January 1, 2000.

In addition, the maximum pretax annual compensation that may be contributed was raised from 4% to 6% (except for employees covered by a certain collective bargaining agreement who may continue contributing up to 10% through December 31, 2000, after which time their maximum deferral percentage will decrease to 6%).

($ in 000's)