The Conservative Caucus is sponsoring a public memorial service Sunday for Rep. Larry McDonald (D-Ga.) and the other 268 people who were killed when the Soviet Union shot down a South Korean jetliner last week, but the group plans to exclude any Soviet correspondents from covering the event.

Fran Gemma, a spokeswoman for the group, said that any identifiable Soviet reporters who try to cover the 2 p.m. service at Constitution Hall will be denied entry, but acknowledged that some could walk in as part of the general public.

"Out of the memory of these people," Gemma said, "the country that was responsible for their death shouldn't be given any special considerations, such as being in the press section." She said she thought of the anti-Soviet gesture earlier in the week as the two-hour service was being planned and that Howard Phillips, head of the Conservative Caucus, approved the exclusion of the Soviet correspondents from Tass, Izvestia and Pravda.

But Evgeny Egorov, the bureau chief here for Tass, the Soviet news agency, said the conservative group "need not bother with its exclusionary action , because we were not going to cover it anyway."

"It just gives a lie to their claim of freedom of the press," Egorov said.

Leonid Koriyvin, an Izvestia correspondent, said he did not know of the event, but declined to comment on the ban on Soviet coverage of the service. "It is unusual in my practice to be interviewed," he said.

William J. Small, president of United Press International, protested the ban. "It does no service to understanding when any group prohibits news coverage, even by newspeople from countries or organizations that it finds repugnant," he said.

The Conservative Caucus, a lobbying group that claims 400,000 members, has taken out full-page advertisements about the memorial service that feature a large picture of McDonald, a longtime conservative hero. McDonald's widow, Kathryn, and his children are expected to attend.

Gemma said that the U.S. Navy Band and the Liberty Baptist College choir will perform a variety of patriotic selections. The scheduled speakers include Phillips, evangelist Jerry Falwell, Rep. Philip M. Crane (R-Ill.) and South Korean Ambassador Byong Hion Lew.