PORT-AU-PRINCE, HAITI, JAN. 15 -- Haiti's supreme court today barred five associates of former dictator Jean-Claude Duvalier from running in Sunday's presidential election, contributing to fears here of violence at the polls.

Among those excluded from the election were Claude Raymond, Duvalier's one-time Army chief of staff, and Clovis Desinor, a former Cabinet minister. The two men, who were barred from the election that was called off on Nov. 29, are widely suspected of supporting the attacks on polling places by right-wing gunmen that killed 34 people and scuttled the vote.

The supreme court granted a concession to the "Duvalierists" by permitting three lesser known former associates of the dictator to run. But the decision, along with heightened security measures, suggested that the Army-led government was preparing for a possible confrontation with Duvalierist gunmen, many of whom are former Duvalier militiamen called Ton-Tons Macoutes.

Many Haitians say the Army purposely allowed the gunmen to ruin the independently run November election and plan to rig Sunday's polls to stay in power.

Army and police officers set up checkpoints on Haiti's roads and searched vehicles and passengers for weapons.

"They never did this search for guns before the last election," said a middle-aged driver in the central town of St. Marc who did not want his name to be used. "This time they want to stop the Macoutes instead of helping them."

The Army stood by during weeks of shootings and arson before the November vote, and witnesses reported that soldiers joined in some attacks on Nov. 29.

{In a televised speech Friday night, military junta leader Lt. Gen. Henri Namphy promised a safe transition to democracy "in accord with the profound realities of the country" and called on Haitians to vote, The Associated Press reported.}

Opposition sources said the government is continuing to arrest Haitians organizing a boycott of Sunday's vote, with some reports saying that about 100 persons have been detained this week. Many other opponents of the government have been hiding since Nov. 29.

The boycott call has been led by a coalition of mainstream former candidates and is supported by Protestant and Roman Catholic churches, some of which have reportedly canceled Sunday services to encourage people to stay home. Several dozen Haitians interviewed this week said they believed the boycott would be widespread. Government spokesmen have disagreed.

While government officials claim there is enthusiasm for Sunday's voting, some observers conceded that the long struggle against the military and government has left much of the population exhausted.

The government was installed in February 1986 after Duvalier fled a popular uprising. It permitted some steps toward democracy, overseeing the preparation of a constitution, approved in a referendum last spring, which called for a transition to an elected government next month. But the government and opposition have struggled -- through strikes, protests and arrests -- over who should control the elections.

Especially among the large class of desperately poor Haitians, "it's become impossible to have a prolonged protest or strike that could really threaten" the government, a Port-au-Prince businessman said. Opposition leaders have scheduled a one-day general strike Saturday.

{In Washington, five members of Congress asked President Reagan on Friday to reject the new Haitian elections and refuse to recognize any government that emerges from the balloting, the AP reported.

{Meanwhile, a flotilla of more than 30 U.S. Navy warships participating in Caribbean maneuvers steamed toward Puerto Rico on Friday. Pentagon officials said the ships would be within easy range of Haiti should election-day violence spur an evacuation of the estimated 7,000 Americans there.}