Former Washington school superintendent Vincent E. Reed yesterday resigned as assistant U.S. secretary of education to become vice president for communications of The Washington Post.

Reed, 53, took his job with the Reagan administration last March after five years as the city's school superintendent and 24 years as a teacher, principal, and administrator in the D.C. public schools.

In his new position Reed will be in charge of The Post's public relations and school services programs. Publisher Donald E. Graham said Reed will serve as "the principal spokesman for the paper to the community and for the community to the paper." Reed will have no involvement in news gathering or editorials, Graham said.

Reed said he accepted Graham's offer to work for The Post as "a wonderful opportunity to expand my future and to make a contribution to The Post and the city of Washington."

"I've never been in the private sector before," Reed said, "and I'd like to take a shot at it."

As an assistant education secretary, Reed worked for a department that President Reagan has vowed to remove from the Cabinet. He was in charge of federal aid programs for elementary and secondary schools, which the administration is trying to reduce and hand over to the states through block grants.

Reed's own staff has been cut from 556 to 383 and the amount of aid he administered was trimmed from $5 billion to $3.2 billion.

Yesterday Reed spoke enthusiastically about his job in the education department, where he spearheaded efforts to reduce federal regulations over local schools. He accepted the president's decision to cut federal aid to schools, though he said he had sought more money for the programs.

"I've enjoyed every minute I've been here," Reed said. "I was not dissatisfied at all. I think we've carried the president's program forward. Now I think the offer from The Washington Post will give me an opportunity to help The Post Become a better paper and improve my options for the future."

Reed was one of the highest-ranking blacks in the Reagan administration, which has one black as a Cabinet secretary, Samuel Pierce at Housing and Urban Development, and only two others as assistant secretaries besides Reed. There are seven other blacks with sub-Cabinet rank as commissioners and directors, the White House personnel office said yesterday, out of about 250 appointments at that rank.

When he joins The Washington Post on March 1, Reed will be the only black among the newspaper's 10 vice presidents. Earl K. Chism, the vice president/controller of the newspaper's parent company, also is black and was a vice president of The Post newspaper from 1975 until last year.

As assistant education secretary, Reed has been earning $57,000 a year. He said his salary at The Post will be higher, though the amount was not disclosed.

In a news release yesterday, The Post said Reed not only will head the newspaper's public relations programs, but will also "take on a broad range of special assignments" and oversee its charitable contributions. Graham said the assignments will be worked out as Reed becomes familiar with the newspaper's operation.

"I consider Vince Reed one of the ablest guys in town," Graham said, "and I've had it in the back of my mind that he's the kind of person who can do well in a business. He's shown as school superintendent that he can get results, and he knows the community.

Graham added that in his new position Reed has agreed not to be involved in political activity. During last fall's D.C. school board election Reed endorsed a slate of candidates. He also has been approached by local Republicans as a possible candidate for mayor against incumbent Marion Barry in November.

But in an interview earlier this month, Reed said emphatically, "I don't want to be mayor."

Yesterday Reed said, "I've told everybody who asks: I have absolutely, positively no interest in running for mayor. I'm just not a politician."

As school superintendent from 1975 to 1980, Reed won considerable popularity for wrestling successfully with many of the system's administrative ills and introducing a new competency-based curriculum that started to raise low test scores.

After several years of harmony, he and the school board clashed, and in December 1980 he quit, taking advantage of a sizeable pension. He complained bitterly about interference from board members in school administrative affairs.

Reed yesterday had warm praise for his boss at the education department, Secretary Terrel L. Bell. In a statement Bell said, "We will sorely miss his leadership."

Born 14th in a family of 17 children in St. Louis, Reed is a graduate of West Virginia State College. He began work for the D.C. school system as a shop teacher, working his way up through the ranks to superintendent.

Reed said he expected to remain involved in education through The Post's school services program, under which the newspaper provides copies of The Post and guidebooks to teach reading and composition in D.C. elementary and junior high schools.

Reed recently was named to the governing boards of the University of the District of Columbia and American University and will continue to serve in both posts