Are Salvadorans coming to the United States for jobs or are they fleeing persecution? That question is at the core of thousands of political asylum appeals and lawsuits filed across the country on behalf of Salvadorans.

The U.S. Immigration and Naturalization Service argues that Salvadorans are coming here for jobs and therefore have no right to legal residence. The Salvadorans' attorneys say their clients will be harmed or killed if they return home, and should be given asylum.

According to federal law, a person can be granted asylum if he can prove a "well-founded fear of persecution." The INS often interprets the "fear of persecution" standard as fear of communism and grants asylum claim from those fleeing Nicaragua, Poland, Romania and other socialist and communist countries at a far higher rate than those coming from Salvador and other countries with democratically elected presidents.

This happens, the Salvadoran advocates say, despite the fact that there is often far more violence in Salvador and other countries supported by the United States government.

In fiscal 1987, only 5 percent of the asylum claims filed by Salvadorans were granted, compared with the 85 percent from Nicaraguans.

"War is not the criteria," said Duke Austin, INS spokesman. "Asylum is not weighed on danger. It's weighed on individual persecution {and} it's generally accepted that in communist countries, there is more evidence of individual persecution."

"A lot of these people fear for their lives," said Minor Sinclair, a legal researcher for CARECEN, a nonprofit group providing legal counseling to Central Americans seeking asylum. "There are cases when people were sent back {to El Salvador} and were killed. We are just trying to get the same kind of protection for peasants from Salvador that Chinese tennis players {who defect} or Soviets that jump off ships have."

A congressional proposal to halt deportations of Salvadorans and Nicaraguans pending a thorough study of the dangers in those countries passed the House last July. It is now before the Senate and if it passes there, President Reagan has vowed to veto it.