Penthouse magazine charged yesterday that at least 23 members of the Copley News Service also worked secretly for the Central Intelligence Agency over a 20-year period in Latin America.

The authors of the article, Joe Trento and Dave Roman, said the clandestine arrangement stemmed from a 1953 White House meeting with President Eisenhower at which the late publisher James S. Copley offered the help of the news service he was forming.

Copley, the magazine said, volunteered the news service as "the eyes and ears" against "the Communist threat in Latin and Central America" or "our intelligence services."

The allegations were made in the forthcoming August issue of Penthouse which added that the Copley Press, which also publishes the San Diego Union and Evening Tribune, ran a "little FBI" that funneled hundreds of thousands of unpublished words and pictures about antiwar and black protest movements to the bureau.

Spokesmen for the Copley News Serivice (CNS) and the parent firm, the Copley Press, denied the assertions about clandestine ties with the CIA.

Gerald Warren, the current editor of the Union, and Herb Klein, a former editor of the paper, confirmed that memos were written about protest groups and passed on to executives of the company, but said they did not know whether the memos were then passed on to the FBI.

The CIA and the FBI refused to cmment.

The article, financed in part by the FUnd for Investigative Journalism, said that Copley Press "provided credentials, information and placement of stories for the CIA and the FBI: exchanged intelligence information with the CIA for 'scoops' and editorials, (and) harbored CIA and FIB stories and stories and editorials, (and) harbored CIA operatives on the payroll of the Copley News Service and fed stores to news-service clients at the request of the CIA and the FBI.

Elaborating at a press conference here. Trento, 29, now a reporter for the Wilmington (Del.) News-Journal, and Roman, 31, a former San Diego college teacher and now a freelance writer, said the 20 Copley employees, most of them based in Latin America were all "on a salaried basis."

Trento refused to name any of the 23 or even to describe the nature of the CIA payments. He said he had promised his "sources" not to divulge such details.

Richard G. Capen Jr., senior vice president of operations at Copley president of operations at Copley Press, flatly denied the charges of surreptitious CIA employment.

". . . We have been assured by the highest levels within the CIA that no employees of Copley Newspaper or CNS have been employees of the agency," Capen said.

Warren, former deputy White House press secretary under President Nixon, indicated in a telephone interview that the assurances had been provided to present publisher Helen Copley about a year and a half also when the charges first began to surface. "I'm confident of the assurances Helen got," he said.

Capen protested that the reports of CIA involvement are essentially "old allegations that Copley Newspapers have repeatedly denied over the past two years. One of the authors, Joe Trento, has printed most of these claims in a mimeographed newsletter, San Diego Confidential, and they have been repeatedly denied by us."

For their Penthouse article, Trento and Roman said that they had examined still-secret White House documents in the possession of CIA sources and that these documents confirmed not only Copley's 1953 "eyes and ears" offer but also Eisenhower's response.

". . . Eisenhower told Copley that "your favors are appreciated by the country and will be reciprocated whenever possible," the magazine said.

George Curtis, superisory archivist of the Dwight Eisenhower Library in Abilene, Kan., told The Washington Post that records there show a meeting between EIsenhower and Copley was held on April 25, 1953. Copley vice president William Shea also attended the meeting, which had been requested by Copley's Washington bureau chief, Robert W. Richards. Penthouse identified Richard as a former Officer of Strategic Services officer hired by Col. Ira Coipley to run the Copley Washington bureau before the end of World War II.

Trento and Roman said the current Latin-American editor for the Copley News Service, William Giandoni, "actually fed information to CIA operative William Kelly in 1961 concerning the forthcoming Bay of Pigs invasion." (They said at the pess conference they had no evidence that Giadoni was paid by the CIA.

"Giandoni gladly acceded to the CIA's request for secrecy, writing stories which downplayed the idea that any invasion was in the works at all and proposed that such speculative stories were false," the article said. In response, Giandoni said he once applied for a job with the CIA in Mexico City but "got a form letter back telling me they had nothing available."

Turning to the FBI, Trento and Roman said Copley Press officials regularly funneled reporters' memos and news photographers' pictures about antiwar and other demonstrators to the FBI. "Many reporters were asked for a four-paragraph story and a five-page memo," Roman said of the system.

Warren, who was city editor at the Union from 1963 through 1968, said in a telephone interview that he could recall "passing on memos to my superiors of reporters' views of demonstrators. Where those memos ended up, I really don't know."

Warren indicated he had his suspicions but he added that "I have learned that my suspicions really don't mean much."

Trento and Roman said they had no evidence that any of the secret Copley News Service links with the CIA or the FBI were continuing, Roman said he believed "most of the activity stopped when (James) Copley died" on Oct. 6, 1973. President Nixon praised him at the time as "a close friend and adviser" and said the nation had lost "a noble American."