The U.S. Immigration and Naturalization Service will seek to deport many of the 173 supporters of Ayatollah Ruhollah Khomeini arrested during demonstrations by Iranians here Sunday.

Sources said the INS plans to employ the strict provisions of regulations that were adopted seven months ago as part of a get-tough policy after the seizing of America hostages in Tehran last November.

Apparently fearing deportion, the pro-Khomeini Iranians refused to give their names when they appeared in D.C. Superior Court yesterday to face charges of disorderly conduct stemming from the demonstrations.

However, that tactic could backfire on the demonstrators if they also refuse to identify themselves to INS agents, because one provision of the regulations requires students and other aliens here on temporary visas to provide "full and truthful disclosures of all information requested" by the INS.

The new regulations make it easier for immigration officials to win deportation an alien by requiring him to answer any questions they choose to ask regardless of whether the information in germane. The regulations also make an alien deportable if he is convicted of a crime that carries a sentence of more than a year, even if the alien receives a lighter prison term. s

Just how the INS plans to apply the regulations was unclear yesterday. Both Justice Department and INS officials refused to comment on the move, which apparently was decided upon late Sunday night during high-level discussions between INS director David Crosland and the Justice Department.

One INS official said that immigration authorities believe most of the arrested demonstrators are students who are inviolation of the conditions of their student visas. He said that many of them probably are working without proper authorization while others who are supposed to be studying full-time have dropped out of school.

"If they are here illegally," said one INS source, "then you know what's going to happen to them."

It was a ragtag army of demonstrators who limped or helped each other into the ceremonial courtroom of the D.C. Courthouse yesterday to enter pleas of not guilty before Judge John Hess.

Many of them complained about mistreatment and overcrowding during their overnight stay at the D.C. jail. But a deputy U.S. Marshal called it "quite an acting job. They weren't limping until they reached the stage (courtroom)," he said.

Defense attorney G. Daniel McCarthy told Judge Hess that some of his clients had been mistreated and insisted that their conditions and complaints be made part of the court record. McCarthy said six to eight of his clients were jammed into cells designed to hold two prisoners and that they received inadequate water and medical attention. Two of the men said they had been beaten by jailers one with a pistol butt and one by having his head slammed against a wall.

McCarthy said all 173 of his clients were Khomeini supporters. He said his law firm, Abourezk, Shack and Mendenhall, has represented the Khomeini government since it replaced that of the shah last year.

McCarthy would not comment on why his clients refused to give their names. All but one of the 173, who included 16 women, were charged with disorderly conduct, a misdemeanor which carries a maximum of 90 days in jail and a $250 fine. A court spokesman said they all could have been released, on $250 bond each, if they had given their names.

The others pro-Khomeini demonstrator who remains charged is held under $25,000 bond. He is accused of assaulting a D.C. police officer with a baseball bat.

Charges against two other Khomeini supporters were dismissed because of lack of identification.

A total of 177 persons appeared before Judge Hess yesteray on charges relating to Sunday's demonstration, which pitted three pro-Khomeini groups against the anti-Khomeini Iran Freedom Foundation, whose founder, Ali Akbar Tabatabai, was assassinated in the doorway of his Bethesda home last Tuesday.

A charge of disorderly conduct against Anthony Manley, 25, of 1250 10 St. NE, was continued pending the appointment of an attorney to represent him. Manley is an American who was charged with throwing a bottle at one of the Iranians.

Another demonstrator who refused to give his name, but who apparently was not a pro-Khomeini Iranian, was represented by public defender service lawyer Charles Ogletree. Bond was set at $3,000 in that case, in which the charge was destruction of property.

At the Islamic House, 5714 16th St. Nw, about 40 Moslem students began a hunger strike yesterday to protest what one of them, Mahmaoud Asgari, called the "unjust attack" on pro-Khomeini demonstrators Sunday. The students gathered on the lawn of the house yesterday afternoon to announce the strike. One of them wore a neck brace and anther a head bandage and several displayed bloody shirts which they said were the result of attacks on them by police Sunday.

Meanwhile, the search for the alleged killer of Tabatbai continued.

The FBI yesterday got permission from the Algerian Embassy to interview the eight of nine Iranian employes of the Iranian Interests Section about Daoud Salahuddin who is accused of being the triggerman in last Tuesday's killing.

Salahuddin, 29, an American who changed his name from David Belfield when he joined a Moslem sect, was employed at the interest section, housed in the Algerian Consulate at 2139 Wisconsin Ave. NW.