The Securities and Exchange Commission yesterday charged Occidental Petroleum Corp. with secretly creating two foreign companies and spending more than $600,000 for political contributions, gifts and entertainment.

In addition, the SEC said Occiental set up two Swiss bank accounts and deposited $25,000 in a numbered account of unnamed foreign political candidate. The commission said the alleged illegalities began in 1969 and continued to the present.

Without admitting or denying the allegations. Occidental consenled to the SEC complaint filed in federal court here.

The SEC investigation grew out of the revelation that the company's chairman Dr. Armand Hammer made a $54,000 illegal contribution to President Nixon's 1972 re-election campaign. Hammer pleaded guilty to the charge.

Two foreign companies, which were not identified in the complaint, generated income and profits of at least $220,000, the SEC said, but the money was not reported on Occidental's books and records.

The SEC said about $400,000 of company funds were used for questionable or illegal payments to foreign officials.

The commission charged that about $59,500 was transferred from the foreign bank accounts to a secret fund of cash at the company's Los Angeles headquarters.

Occidental, as a part of the settlement, agreed to make a full report on the allegations within 60 days.

In other SEC developments:

Avis, Inc., disclosed in an amended registration statement that a $470.958 foreign payment was under investigation by the commission.

Last November, Avis's audit committee disclosed $425,000 in questionable payments, which were not related to the latest figure.

White & Case, a major New York law firm, agreed to settle an SEC suit growing out of litigation involving a client, National Student Marketing Corp.

Under the settlement, Marion J. Epley III. the White & Case partner who handled the National Student Marketing account, was barred from practice before the SEC for six months and the firm agreed to certain SEC-dictated procedures in dealing with securities accounts.