Sociologist James S. Coleman, who headed a massive influential study favoring school desegregation in the mid-1960s, yesterday strongly supported a tuition tax credit to aid parents of private and parochial school pupils.

Coleman, a professor at the University of Chicago, said he favors the tax credit - which has been voted by the House but is bitterly opposed by the Carter administration - because it would "increase the range of choice of low-income black parents."

Particularly in big cities, Coleman said, where large-scale public school desegregation is unlikely, a tax credit "would increase the opportunity of black parents to escape from schools that they think hurt their children."

Opponents of the measure have contended it would promote segregation, hurt public schools and mainly benefit middle and upper-income groups.

But Coleman siad that because of the relatively modest size of the proposed credit, $100 to $500 per student, "the principal effect would be on lower-income families" sending their children to relatively low-priced schools.

He said "a very large number of black children" already attend low-tuition Catholic schools in big cities, such as Chicago, New York and Washington, with generally positive educational results.

Coleman spoke at a forum on desegregation attended by about 60 persons at Georgetown Day School, 4530 MacArthur Blvd. NW. The forum was sponsored by the Black Student Fund, which during the past decade has aided more than a thousand black students to attend private schools in the Washington area.

He was introduced warmly by Alice M. Rivlin, director of the Congressional Budget Office, who later asked him to deal with the "accusation" that programs to help blacks attend private schools are "detrimental" to public education.

"That's not a valid argument," Coleman rejoined. "Anything that allows for an individual to have greater opportunity can't be bad for the country."

Besides favoring a tuition credit on federal income taxe. Coleman said he supported proposals to give vouchers to parents to use for tuition at public or private schools.

"Parents and children have a better sense of what's good school context for them," Coleman said, "than do professionals who must deal with a very large number of children. I trust the parents and children more than the professionals.

"I think the stronger the private schools are the better it will be for the public schools because the public schools will be forced to be better to stay in business."

Overall, Coleman said, school desegregation since 1954 has had "no effect" on educational achievement of black students.

"In the absence of turmoil," Coleman siad, "there seems to be an achievement increase." But so far, he said, this had been counterbalanced by reduced black achievement in places where desegregation was accompanied by conflict and fear and "distraction from study."

In general, he said, integration has been most successful in well-disciplined schools headed by strong principals.

Coleman stressed that the main finding of his 1966 report, issued by the U.S. Office of Education, was that black students had higher achievement in mostly white schools not because of the skin color of their classmates but because of the middle-class background and "educational resources" that the white children brought from home.

"Increasingly, class is less correlated with race than it was 10 years ago," Coleman said.

Widespread desegregation, he said, has been "enormously beneficial" to the South by aiding its transformation from a backward region to a thriving "Sun Belt."

But he repeated his view, which has attracted controversy for the past three years, that desegregation programs requiring "instant racial balance" through compulsory busing have caused "very serious harm" by speeding the exodus of whites from big cities.