The Washington Post Co. announced yesterday that president and director Larry H. Israel has resigned, effective Feb. 1.

Israel's departure, described by newspaper industry analyst John Morton at Colin, Hochstin Co. as "very surprising," comes in the wake of Broadcasting magazine report that "he has been importuned to consider other ventures in communications, primarily broadcasting."

Broadcasting also reported that the 57-year-old Israel has been mentioned for a post in the Carter administration.

Israel wa unavailable for comment on these reports yesterday but the company issued a statement by Israel, which said:

"After 25 years in positions of major responsibility in the communication industry, I have decided it is time to engage in new activities . . . I feel that this is an appropriate time for me to shift my energies to several long-standing personal interests and to develop other projects in television and related fields."

The Post Co. said Israel indicated he intends to maintain his residence in Washington and that the firm's board of directors is expected to designated chairman Katherine Graham as president, a position she held from 1963 to 1973 when she became chairman.

The Washington firm owns The Post newspaper, the Trenton (N.J.) Times, Newsweek magazine, four television stations and one radio station. Israel joined the firm in August 1968 as chairman and president of Post-Newsweek Station, the broadcasting subsidiary. He became president of the parent firms in May 1973.

Before coming to the Post Co., Israel was president of the Westinghouse Broadcasting stations. He is a graduate of the University of Missouri School of Journalism.

In a statement included in yesterday's announcement, company chairman Graham said:

"Larry's record as an innovator in broadcasting has been widely recognized, especially in television journalism and public-affairs programming, in setting higher standards, for children's programming, and in advocating greater access to the broadcast media by political candidates. However, we respect Larry's desire to pursue other interests and explore new opportunities in the years ahead."

Israel's statement said the Post Co. "has had its most successful year in 1976."