As many as a quarter of a million people in the Washington metropolitan area, or one in every 12 residents, are thought to be recent immigrants, according to a new study released last week.

The study, compiled by demographers Eunice and George Grier of The Grier Partnership, is a preliminary report on the growing number of persons who have settled here after leaving their countries because of religious, political or economic difficulties. It is thought to be the first study of its kind done in Washington.

The study was commissioned by the Community Foundation of Greater Washington, a nonprofit organization that receives and distributes funds from individuals, foundations and national corporations. Foundation chairman Lawrence S. Stinchcomb said his organization wanted an assessment of the needs of the "newcomers" in order to better assess the increasing number of funding requests it is getting from local refugee assistance programs.

"We were not surprised at any of the issues or tensions the Griers came up with, but we were surprised with the numbers of people who have come into the community," Stinchcomb said. "Our assessment is that this is a bigger issue than we anticipated . . . the numbers coming in are bound to have a major impact on the community."

The "newcomers" studied by the Griers do not include foreign employes of international organizations in Washington or immigrants who came to the U.S. with work visas because of some special skill.

The "newcomers" the Griers identified included officially sponsored refugees, people who received asylum, and illegal aliens whose "only point in common is that they are here because of conditions that made it impossible, or at least difficult, to continue to live in their own homelands."

Acknowledging that their figures are rough, the Griers based their conclusions on 1980 census data and on estimates given by officials working with the refugees. Of the total estimated population of between 200,000 and 250,000, the largest group is Spanish-speaking. In the 1980 census, that group numbered 93,686.

"Given the undercount problem, as well as the fact that migration to the area of Hispanics, especially Central Americans, has continued in the nearly three years since the census was taken, at least some of the estimates given by our respondents for the current number of Spanish-origin residents do not seem far removed from the census totals," the report said. "The most commonly heard estimate is around 150,000, of which about 60,000 are often estimated to be Salvadorans. Most of these have come here quite recently."

The second largest groups are the Asians and Pacific islanders who numbered 88,498 in the 1980 Census.

Exact numbers for illegal aliens are unavailable.

The District is thought to have between 2,500 and 3,000 "newcomers." Other concentrations are in Arlington, central Bethesda, Takoma Park, Hyattsville, Herndon, Manassas and Springfield. The Griers found that the refugees are "becoming increasingly dispersed throughout the area" as they move in search of lower priced housing.

In their two-month study, which was financed by a $5,000 grant from the Greater Washington Research Center, the Griers identified five areas of difficulties for newly arriving refugees: jobs, housing, health care, differences in language, and culture and community tensions.

Tension among different newcomer groups and between the refugees and native Americans was cited by many of the people interviewed by the Griers as "a problem which has received far too little attention and which may become more widespread and difficult in the months to come," particularly if difficult economic times continue.

"In part, these tensions result because people in the established community--especially black Americans--fear that the newcomers may take jobs and housing away from them," the study said. "Employment is the most common source of conflict between the two groups."

The study took two months and involved interviews with 31 people, both American and foreign, who work with refugees.

Washington's status as the nation's capital was one reason the Griers found for its popularity with "newcomers," who are accustomed to the capital being a place of opportunity in their countries. Many of the foreigners said that they came to Washington because they knew someone in the State Department or the military here whom they had met overseas.

Other reasons for Washington's popularity were that it was found to be more tolerant of foreigners than other sections of the country and that its service-oriented economy afforded more employment opportunities than industrial towns.

In other findings, the study disclosed that a fourth of all students in the Arlington County Schools speak some language other than English in the home, that nearly half of the adult Asian population in the area has had four years of college, and that almost half of the adult Spanish-speaking population has had some college education.

The increase in "newcomers" in the local area "should be recognized for what it is: part of a worldwide phenomenon" that has created about 10 million refugees throughout the world, the Griers stated.

"They are usually in the U.S. because they wanted to live here, not because they had the good forture to be born here," the Griers said. "They have usually gone through nearly incredible hardships before arriving in this country. We feel they are enriching the community and making it a more interesting place to live."

Arthur S. Flemming, chairman of the board of the Community Foundation, said that the study was not meant to debate the policy issues involved in the influx of the immigrants, but rather to help determine their specific requirements.

"We must confront the fact that they're here," Flemming said, "and have some genuine needs."