A concerted, eight-year effort by the South Korean government to influence members of Congress with cash, gifts and parties was outlined publicly for the first time yesterday with the unsealing of a 36-count felony indictment against Korean businessman Tongsun Park.

The indictment, which had been sealed since being handed down by a federal grand jury in Washington Aug. 26, charges that Park was a secret agent of the Korean government who conspired with two former directors of the Korean Central Intelligence Agency and former Rep. Richard T. Hanna (D-Calif.) "to defraud the citizens of the United States" of their right to have their elected officials in Congress act free of bias and corruption.

It alleges that Park, "with the knowledge and under the direction of KCIA," worked with Hanna to make campaign contributions and cash gifts, promote trips to Korea and sponsor elaborate parties at the Korean-government-inspired George Town Club in Washington in the attempt to gain favor with members of Congress.

Justice Department officials said they knew of no other case where such wide-ranging charges have been made about the lobbying efforts of a foreign government.

Attorney General Griffin B. Bell said yesterday in announcing that the indictment had been unsealed that would ask President Carter to appeal personally to South Korean President Park Chuung Hee to have Tongsun Park, "who is now a fugitive from American justice, returned to the United States."

Park left Washington for London last fall, and on Aug. 18 returned to Korea, where he's been since.

Hanna received more than $100,000 from Park from 1967 to 1975, the indictment charges, in return for his help in trying to influence other members of Congress. In effect, the 30-page indictment claims that Hanna was Park's agent on Capitol Hill.

Bell said other indictments might follow. "The investigation is continuing," he said. "We're in the season, and we'll have to see what the harvest will bring."

While Hanna is named as the recipient in the two bribery statue charges against Park, he was named only as an unindicted co-conspirator, along with the two former KCIA directors.

Benjamin R. Civiletti, head of the Justice Department's Criminal Division, said yesterday that Hanna was not cooperating in the investigation. Cooperation with the prosecution is usually the sign of an unindicted coconspirator. Civiletti indicated that the department has insufficient evidence to indict the former congressman on such counts.

Justice Department attorneys have expressed concern that evidence against some potential congressional targets of the investigation might be inadmissible because the Constitution's speech and debate clause protects legislators in their actions.

Hanna's attorney, Charles McNelis, said yesterday that his client flatly denies any implication that he was bribed.He noted that Hanna had a publicly known business relationship with Park while in Congress. Any favors he did for South Korea came from a "long-standing friendship toward that country," he added.

The indictment names 20 House members and four senators who received money from Park. Most of the donations to House members have been mentioned before in stories (See KOREANS, A10, Col. 1) (KOREANS, From A1) about the progress of the more than year-long Justice Department investigation, and most would have been legal at the time if the recipient didn't know that Park was foreign agent.

The indictment does mention $10,000 in contributions to the 1971-72 governor's race of then Rep. Edwin W. Edwards (D-La.), and $1,000 to Rep. William Broomfield (R-Ill.). Both have previously denied getting any such money from Park.

In addition, the 30-page outline of the charges for the first time mentions present and former senators who got money from Park. They are former Sen. Joseph M. Montoya (D.N.M.), $3,000 in 1970; former Sen. Jack Miller (R-Iowa), $3,000 in cash in 1972; former Sen. Stuart Symington (D-Mo.), $500 in 1970, and Sen. Harry F. Byrd Jr. (Ind-Va), $500 in 1970.

The indictment against Park and the stated complicity of the Korean government in the lobbying scheme come at a time when pressure is building on Capitol Hill against South Korea.

Rep. Bruce F. Caputo (R.N.Y.), a member of the House Committee of Standards of Official Conduct, which is conducting a parallel but separate investigation of members who took gifts from the Koreans, said yesterday he planned to introduce an amendment to the new budget resolution cutting funds by $114 million, an amount equal to U.S. aid to Korea.

He said he would do so because the Korean government has refused to cooperate ing get Tongsun Park returned to the United States.

The State Department also has been concerned about how the investigations and publicity about the Korean lobbying effort will affect future votes on aid to the Park Chung Hee regime.

A State official noted that the planned withdrawal of U.S. troops from Korea has been coupled with a promise of aid to improve the Korean armed forces. "How many of them [members of Congress] will vote money to Korea after seeing that the Koreans have been paying money here?" he asked. "The troop withdrawal may have to stop if Congress does not come up with funds to beef up the Koreans."

Each new aspect of the investigations "complicates withdrawal more," he added.

Attorney general Bell said yesterday that the indictment against Park was unsealed, in Part, because its existence was made known last week through press reports.

The first count of the indictment charges Park with conspiracy to defraud the United States, and outlines a scheme it says started in 1967, when Tongsun Park and Hanna and Korean government officials agreed that the Washington businessman would be the exclusive agent for selling American rice - much of it U.S.-subsidized - to Seoul.

It was part of the conspiracy, the indictment claims, that Park gave a part of his rice commissions to Hanna and other members of Congress. The George Town Club, an exclusive dinner club owned by Park in Washington, was also used by Park and Korean officials "for the purpose of holding fun-raising affairs and parties" for American politicians, it charges.

The conspirators also tried to encourage trips to South Korea, where other Korean government officials would lobby the Americans, according to the charges.

In 1970, Park began issuing checks to the campaigns of many members of the House and few senators, a pattern which continued for several years. Some times contributions were in cash.

In 1971, the indictment adds, Hanna sent a letter to then KCIA Director Lee Hu Rak recommending that he resolve a dispute between Park and the Korean embassy in Washington over "their lobbying and other influencing activities in the U.S. Congress."

The second and third counts of the indictment charge Park with violations of bribery statutes because of his payments to Hanna.

The fourth count says Park was acting as a representative of the Korean government in his actions and failed to register with the Justice Department as required by law.

The fifth and sixth counts charge him with making illegal $3,000 cash campaign contributions to Reps. John Brademas (D-Ind.) and John J. McFall (D-Calif.). Both have acknowledged receiving the money, but claimed they did not know at the time that Park was an agent of a foreign power. The next 29 counts in the indictment charge Park with mail fraud violations, all relating to checks he sent to Hanna from 1973 through the end of 1975.

The final count says that Park's Washington company, Pacific Development, Inc., was used to conduct a pattern of racketeering activities, including the funneling of money to Hanna. Conviction on that charge would allow the United States to seize the assets of the corporation.

Bell said yesterday that it would be unfair to conclude that the members of Congress named in the indictment are targets of the which have not been mentioned before and who received contributions in 1970, are Ross Adair (R-Ind.), $500 in; Peter Frelinghuyesn (R-N.J.), $500, and Chester Mize (R-Kan), $500.

Others whose names have appeared in various newspaper accounts before, and who also got money in 1970 include Reps. Morris K. Udall (D-Ariz.). $300; William Ayres (R-Ohio), $500; Thomas Kleppe (R-N.D.) and later Secretary of the Interior, $500; Frank Thompson (D-N.J.), $100; Lawrence Hogan (R-Md.). $500; Melvin Price (D-Ill.), $500; Thomas Foley (D-Wash.), $500; Kika de la Garza (D-Tex.), $500; Spark Matunaga (D-Hawaii), now a senator $500; John Murphy (D-N.Y.), $500; Nick Galifianakis (D-N.C.), $500.

Foley is named in the indictment as having made a call on Tongsun Park's behalf to an executive branch official in 1971 or 1972. An aide to Foley said yesterday that the congressman couldn't recall making such a call.