WINSTON-SALEM (AP) _ Testimony has ended in a civil case against 45 Ku Klux Klansmen, Nazis and officials accused of violating the rights of five members of the Communist Workers Party killed in a bloody confrontation six years ago.

It is the third time the deaths have been the subject of court action. Two previous cases ended with verdicts of innocent.

The last of 101 witnesses testified Tuesday in U.S. District Court. Judge Robert Merhige has recessed court until Monday when final arguments are expected to begin. Attorneys expect the arguments to take about two days.

Sixteen plaintiffs, including four widows and a widower, have filed a $48 million suit against 20 Klansmen and Nazis, four federal agents and 21 police and other officials of the city of Greensboro, where the slayings occurred on Nov. 3, 1979.

The defendants are accused of conspiring to deprive those who died and survivors of their civil rights by disrupting their ''Death to the Klan'' rally and march or by allowing the disruption to occur.

Eleven plaintiffs have said they were wounded or falsely arrested, but Merhige dropped some of the false-arrest claims from the suit last week.

''I think we really put on a solid case for the first time,'' said attorney Pam Distefano of the Greensboro Civil Rights Fund, which is representing the plaintiffs.

''We don't feel that in the two criminal trials the truth was allowed to come out,'' she said.

In 1980, an all-white state jury found six Klansmen and Nazis innocent of murder. Last year, another all-white jury found nine Klansmen and Nazis innocent of federal civil rights conspiracy charges. Defense lawyers contended that the Klansmen and Nazis fired in self-defense after the demonstrators provoked a fight.

A jury of four white women, one black man and a white man is hearing the civil case.

The plaintiffs presented 75 witnesses in eight weeks of testimony. They were followed by four defense witnesses for the federal defendants, six for the city and 12 on behalf of the Klan-Nazi defendants in only six days of testimony.

The plaintiffs say federal agents and city officials allowed agents provocateurs to help plan the confrontation. The agents, police and other officials say they acted properly, and the Klan-Nazi defendants say their rights were violated because the demonstrators attacked them first.