The Central Intelligence Agency planted false information with the American press, congressional leaders and the United Nations about the 1975 civil war in Angola, former CIA official John Stockwell charged here yesterday.

Stockwell, who headed the CIA's Angolan task force, said the intelligence agency sent its own propaganda specialists to Africa in 1975. The specialists secretly coordinated an information compaign for two of the three competing Angolan forces.

In addition, Stockwell said the CIA set up a small task force in a New York hotel room to fund and advise the Angolans on a daily basis when they came to the United States to plead their case. To U.S. officials and reports, the Africans distributed CIA-prepared propaganda that Stockwell said was sometimes "false to the point of being ludicrous" and othe times "simply inaccurate."

At a news conference, the 41-year-old Stockwell also said that former CIA director William E. Colby and former secretary of state Henry A. Kissinger both gave inaccurate information about the CIA's role in the Angolan war to congressional investigating committee in 1975 and 1976.

Stockwell, who resigned from the CIA last year, made the changes yesterday in connection with the publication this week of his book, "In Search of Enemies." The book was not submitted to the CIA for prior approval.

The Senate Intelligence Committee has investigated Stockwell's charges as part of a broader review of "U.S. actions in Angola," a committe spokesman said yesterday.

Findings approved three weeks ago by a subcommittee are scheduled to be presented to the full committee Thursday. But the spokesman declined to say whether the conclusions support Stockwell or Colby.

The subcommittee interviewed Stockwell for five days in closed sessions last summer and examined CIA documents, the spokesman said, as well as examining previous testimony from Colby and Kissinger.

The CIA, meanwhile, continued to decline comment on the Stockwell allegations. A spokesman said yesterday that the agency had not been aware the former official was writing a book, and thus had not been given the chance to review it for classified material.

The Justice Department has filed suit against Frank Snepp, another former CIA official, charging he broke the terms of his employment contract with the agency by refusing to submit for review his book about the fall of Vietnam.

In that suit, however, the government has made no claims that Snepp disclosed classified material. Stockwell acknowledged yesterday that he had used classified informationin his book, but said he exposed no current operation and changed the names of agents.

Terrence B. Adamson, a spokesman for the Justice Department, said yesterday that while there had been no formal communication yet from the CIA, "I am sure there will be consideration of legal action" against Stockwell. He said Stockwell's unauthorized publication "is an example of why we're trying the Snepp case, to see if the contract is enforceable."

At his news conference yesterday, Stockwell said he made up his mind to write a book about the Angolan episode before he left the CIA a year ago. He refused to sign the intelligence agency's standard secrecy pledge when he left, he said, despite a half-hour of persuasion by a CIA security official.

Stockwell said he did not take any documents when he left but did have a complete set of notes he kept during the Angolan conflict. "I also had the opportunity before I left to read most of the most sensitive documents on the subject," he said.

On Sunday, Stockwell said, he telephoned CIA Director Stansfield Turner to let him know that the book would be published this week and that he would be appearing on the CBS-TV show "60 Minutes" that day to discuss its contents.

The call to Turner, said Stockwell, was intended as "a gentlemanly gesture" but "it didn't turn out that way."

Turner lectured him about responsibilities as a former intelligence official and reminded him that the CIA had gone to court against Snepp, according to Stockwell, who said, "I took that as a threat." He said he as already approached the American Civil Liberties Union, which is defending Snepp.

Stockwell told reporters that while the CIA's Angolan propaganda program was carefully organized he could recall only two specific cases in which a U.S. newspaper published articles that the CIA had a hand in preparing. Both articles appeared in The Washington Post.

Sen. Dick Clark (D-Iowa), chairman of the Foreign Relations subcommittee on Africa, said yesterday he is reviewing for "truthfulness" the testimony given by Kissenger, Colby and CIA officials at the time the Senate voted to cutt off CIA aid to Angola.

A Clarke aide said Stockwell's story raised questions about the nature of the previous known CIA involvement in Angola and about how much was disclosed by administration officials at the time.

New to the subcommittee the aide said were Stockwell's allegations about U.S. collusion with South Africa, the use of CIA officers as advisers in Angolia and CIA recruitment of mercenaries, and about the alleged theft of $1.4 million in CIA support money for Angola by Mobuto Sese Seko, president of Zaire.