Lack of adequate financial support by member churches has forced drastic staff and program cuts in the social action unit of the National Council of Churches.

Although NCC leaders were reluctant to read long-term trends into the fiscal problems of its Division of Church and Society, the failure of major denominations to fund the cooperative social action agency appears to reflect a withdrawal of Protestant churches from their heavy involvement in social issues during the height of the civil rights and antiwar struggles.

The division, its staff already a fraction of the number deployed a decade ago, last week dropped five of its 16 professional employes. The dismissed persons had headed a range of programs involving welfare reform, full employment, criminal justice, racial justice, domestic hunger and poverty.

The Rev. Dr. Lucius Walker Jr., who heads the division, said the remaining staff members would be able to carry on some of the work that had been done by the dismissed officials.

One program area that will be wiped out, however, was the council's work with Haitian refugees in Miami, which included representing them before government agencies in Washington.

Under the NCC's complicated financial structure, the 31 member denominations may pick and choose which of the council's programs or areas of activity they want to support financially. Other major divisions of the council deal with Christian education and overseas missions and service.

Only the social action division, which traditionally deals with some of the most controversial issues, is in trouble financially, said a council spokeswoman.

Even within a division of the council, member denominations may choose which projects they will support, which projects they will support, which Walker said was one of the factors in the present crisis.

"There is," he said, "a tendency among denominations to designate their contribution to a specific program" without supporting the central administrative budget of the division.

He cited one denomination that gave $20,000 for the division's special program for full employment but only $4,000 to the division's core budget.

The core budget supports, in addition to administration, the council's programs in religious and civil liberty, international affairs, racial and economic justice, justice for women, and specialized education and training projects.

Walker also cited inflation as one of the causes of budget problems.

The deficit facing the division, accumulated over several years, is about $300,000. It will be covered by loans from other parts of the Council. The church and society division's total budget is $88,880. The total program budget of the council is just over $20 million.

The social action programs supported in the 1960s by some mainline Protestant churches, particularly their aggressive support of civil rights and antiwar efforts, cost them both membership and financial support.

In the more introspective mood of the post-Vietnam era, liberal Protestantism, the bulwark of the NCC, has tended to be overshadowed by the born-again movement, which traditionally has been less concerned with social action.