The four-month-old trial detailing the secret U.S. role in smuggling Ethiopian Jews out of Sudan to Israel has left an indelible mark on Sudan's political life and many here expect that it will have a long-lasting effect on relations between Khartoum and Washington.

The actual defendants in the trial -- televised nightly and now apparently drawing to a conclusion -- are former vice president Omar Tayeb and four aides. But the new Sudanese government also has used it as a way of illustrating what it sees as the failings of ousted president Jaafar Nimeri and of examining the roles of a number of American officials, including Ambassador Hume A. Horan, in detail sufficiently embarrassing to have provoked official U.S. complaints, according to western diplomats and Sudanese officials.

Sudanese were shocked last year at the disclosure abroad of a joint Israeli-American civilian charter airlift of the Ethiopian Jews, called Falashas, and then of a followup U.S. Air Force evacuation of those left behind earlier. Now, they have learned from the trial that Israel and the United States were smuggling Ethiopian Jews out of Sudan as early as 1980.

Prosecution witnesses have charged that the Central Intelligence Agency paid Tayeb $2 million -- donated by "Jewish organizations concerned with Jewish resettlement" -- for Sudan's cooperation.

Tayeb was quoted by a prosecution witness as saying the airlift was necessary "to win over American public opinion and the support of Zionist groups against the mounting criticism of human-limb amputations ordered by Nimeri in the name of Islam."

Tayeb denied any bribe was involved but said that he had cooperated when "the transportation request was made by a friendly country that supports Sudan politically, economically, diplomatically and in the military and security fields."

Sudanese officials of the current government, which overthrew the staunchly pro-American Nimeri last April, deny any intent to single out the United States for criticism in the trial. With a bankrupt economy, a civil war in the south, and elections planned in April, they repeatedly have thanked the United States for its massive aid. They also have sought U.S. understanding for what they present as a campaign to purge the effects of Nimeri's corrupt 16-year reign and prepare the country for democracy.

Sudanese officials do not contest the official U.S. argument that Nimeri's aid was enlisted in the humanitarian evacuation of stranded Falashas, many of them ill, in keeping with the Sudan's record of welcoming refugees.

But many normally pro-American Sudanese say they are confused by what they perceive as the Reagan administration's overreaction and double standards.

Charging that Horan protested the broadcasting of the trial after having tried initially to have it held in closed-door sessions, a Sudanese minister said privately, "Why should the United States practice freedom of the press at home and want to suppress it abroad?"

U.S. protests against what it felt were derogatory opening remarks by Attorney General Omar Abdelati appeared to backfire. Editorials in the Sudanese press called for Horan's recall.

Sources here said that the U.S. Embassy also delivered to Foreign Ministry officials letters from pro-Israeli congressmen threatening an aid cut if televising of the trial continued.

U.S. officials acknowledged that Horan had complained about the charges made in the trial and the televising of it, but they said the complaints were aimed at what Washington saw as a distortion of the humanitarian purpose of the airlifts. U.S. officials refused to comment on the reports that the embassy had passed on congressional criticism.

Other western diplomats said the U.S. Embassy, in talks with them, had made no secret of its complaints to Sudanese authorities.

Whether the scars the trial leaves on bilateral relations will be permanent is unknown, but already one side effect has been a general tightening up on private voluntary organizations active in famine relief, one of which complied with a government order to leave the country after trial testimony implicated its staff in the Jewish airlift.

The departure of more than 1,000 Ethiopian refugees with U.S. entry visas is being delayed as a result of suspicions aroused by the trial about all relief operations.