Members of the House Committee on Standards of Official Conduct are locked in an 11th-hour dispute over whether to hold public or secret trials of colleagues accused of wrongdoing in the investigation of South Korean influence-buying.

The committee is to meet again today to continue debate on the issue. The members spent several hours on the subject last Thursday without reaching a decision, sources said.

Attorneys for Rep. Edward R. Roybal (D-Calif.) precipitated the internal squabble by arguing that the congressman's disciplinary hearing - set for tomorrow - should be held in executive session.

Roybal is charged with lying about $1,000 in cash he received from South Korean lobbyist Tongsun Park in 1974.

His attorneys argued that any proceeding against him be closed because House rules call for secret sessions when testimony "may tend to defame, degrade or incriminate any person."

Rep. John J. Flynt Jr. (D-Ga.), the retiring ethics committee chairman, and Rep. Charles E. Bennett (D-Fla.) seemed sympathtic to that argument at Thursday's meeting, sources said, while some other members pushed for open hearings.

Attorneys for the committee's special investigating staff countered in a brief filed Friday that the hearing could be public because Roybal has already had a chance to refute the charges in executive session and the committee voted the evidence was reliable enough to support a public charge.

The brief, signed by chief counsel John W. Nields Jr., likened the earlier proceedings to grand jury deliberations, the public charge to an indictment, and the proposed hearing to a trial.

He also noted that secret sessions now would be contrary to the committee's reading of the rule when it permitted Tongsun Park to give "defamatory" testimony against Roybal and about 30 other members in open hearings earlier this year.

To have closed hearings "would risk the appearance that the committee was simply using the rule to conceal from the public the evidence upon which it will base its ultimate finding of fact, thus seriously jeopardizing public confidence in those findings," Nields said in the brief.

Another source close to the committee added: "Who's going to believe it if they exonerate these guys after secret trials?"

The proceedings against Roybal and Rep. Charles H. Wilson (D-Calif.) have been scheduled tentatively for this week, with those against Reps. John J. McFall (D-Calif.) and Edward J. Patten (D-N.J.) the week after.

Each is charged with accepting cash from Park in violation of House rules. Wilson also is accused of lying about the money to investigators.

The ethics committee's preparations for the disciplinary hearings have been hampered by the absence of members campaigning for the November elections. Thursday's meeting, for instance, was held up for hours because a quorum wasn't present.

The committee is still awaiting a response from former South Korean ambassador Kim Dong Jo about payments he is suspected of making to some present House members, but an answer is expected soon, it was learned.