The Securities and Exchange Commission has evidence that money paid by an American defense contractor for the privilege of selling military equipment to South Korea was channeled by the Koreans to U.S. congressmen and other officials.

Among the South Koreans under scrutiny by the SEC in connection with the alleged bribery scheme are a military attache with the South Korean embassy here and a former South Korean government official.

The Washington Post has assembled details of the SEC investigation from documents the SEC has filed in court here and from sources familiar with the investigations.

According to these soucrces, E-Systems Inc., a Dallas-based elecronics firm, paid over $1.3 million to agents here for Korean Research Institute (KRI), a Seoul-based marketing consultant firm, to obtain contracts to sell military radios to the South Korean government.

The SEC believes the money paid by E-Systems to KRI was deposited in KRI bank accounts in the United States and then transfered to several other South Koreans here.

According to the court documents, the SEC staff also believes from evidence it has that the money may then have been used to make illegal payments in this country, apparently to congressmen and other officials.

The SEC investigation has begun to parallel a separate Justice Department and federal grand jury probe of widespread attempts by South Korean agents to create a favorable legislative climate for South Korea here with bribes to congressmen and other U.S. officials.

According to Justice Department sources, its investigators have evidence that South Korean businessman Tongsun Park, at the directions of South Korean President Park Chung Hee, dispensed between $500,000 and $1 million annually in cash, gifts and campaign contributions to congressmen here during the 1970s.

Tongsun Park, according to these sources, financed the influence-buying with money he received as commission on rice sales by U.S. companies to the South Korean government. Investigators have recently noted that Tongsun Park commingled this money with commissions from other international business deals.

The SEC investigation is the first to determine whether E-Systems knew of any illegal use of the money it was paying KRI.

The first indication that the SEC had evidence of money being funneled through KRI to U.S. officials appeared in a motion the SEC filed in U.S. District Court here to enforce subpoenas of three men - Kim Jong-Ho, Kim Myung-Jae and Young C. Chung - who allegedly received money from KRI.

According to the court documents, the SEC was told by New York attorney John J. Kim, that the two other Kims and Chung would not appear in response to the subpoena.

Attorney Kim represents two other men, Yoo Jong-Ho and Howard P. Lee, both of Los Angeles, who are described in other SEC documents as KRI agents in the United States. He has opposed enforcement of the SEC Yoo had Lee subpoenas in Los Angeles. Attorney Kim also represents the Korea Trade Promotion Center, a registered foreign agent for the South Korean government.

Col. lee Kyoo-Hwan a military attache at the Korean embassy here, is under scrutiny by the SEC for his alleged connections to KRI, Yoo and Howard P. Lee, according to sources familiar with the investigation.

When contacted by a reporter, Col, Lee said that he had been in contact with Attorney Kim to determine if he was related to Howard P. Lee. According to Col. Lee, Attorney Kim told him he ws not related to Howard P. Lee and need not inquire further into the investigations.

Col.Lee has never been identified publicily as being connected to KRI and has not been contactd by the SEC. He not been explain why he contacted Attorney Kim.

According to diplomatic records, Col. Lee is a former aide to the chief of staff of the Korean army, served as a battalion commander in Vietnam during the war, and in various logistical and procurement functions since then. Lee declined to discuss what he does now at the South Korean embassy.

The SEC subpoenas of the two Kims and Chung call for all correspondence and other documents with others involved in the case, including Dr.Park Chung-Soo, a university professor in South Korea who once served as an aide to former prime minister Chung II-Kwon.

Dr. Park Chung -Soo visited U.S. at least twice a year. Last January he accompanied his wife LeeBum Joon, a prominent Korean Congresswoman, on a trip to Washington largely devoted to her visits with U.S. congressmen. During that trip, Washington businessman Kim Hancho hosted a dinner party for Dr. Park and South Korean Rep. Lee that was attended by South Korean Ambassador Hahm Pyong-choon, the KCIA station chief here, Kim Yung-Hwan, and Col. Lee

Dr. Park returned here last October, according to source in the Korean community, to try to establish informal contact with members of the Carter campaign staff on behalf of the South Korean government. Carter campaign officials who are now working in the White House did not return a reporter's phone calls yesterday.

Donald O. Clark, a partner in the Atlanta law firm of King and Spalding, and until December the honorary consul general for the Republic of Korea in Atlanta, said he did not know Dr. Park.

Clark said the Korean government asked him for an appraisal of Carter's position on South Korea during the campaign. Clark said his only information came from Carter's public statements. Present and former partners in Clark's law firm include Carter confidant Charles Kirbo, White House aide Jack Watson Jr. and Attorney General Griffin Bell Jr.,

Clark said if the Korean government had wanted to contact Carter's aides, it would have likely contacted them through him. By December, when the Korean government installed a regular consul general in Atlanta and Clark resigned his position, the government had mde no such contact Clark said.