The Prince George's County Council delayed action yesterday on a housing bill that could affect discrimination cases brought to the county Human Relations Commission.

The measure was sent to the county's legal office for further study after questions arose about its precise effect on unmarried couples' rights to buy homes in the county.

Council member Jo Ann T. Bell, who was not at yesterday's meeting, asked that the council postpone action on the bill, which she sponsored.

Bell said that she had understood that her bill would apply to discrimination only on the basis of religion. But the final measure, drafted at the county's legal office with the help of the rights commission, included a clause banning discrimination based on marital status or "lack thereof."

Such a change would mean a major policy shift for complexes such as Greenbelt Homes Inc., a cooperative development of 1,600 town houses that bans unwed couples. Margaret Hoganson, president of Greenbelt Homes, wrote a letter to Councilman Richard Castaldi yesterday saying that her corporation has "grave concerns" about the proposed change. The policy evolved when the complex was built in the 1950s, she said. "I think they wanted a family community, and this was the way they went about it."

Bell contended yesterday that the Human Relations Commission's attempt to amend the marital status provision constituted an "end run" designed to slip a potentially controversial measure past the council.

Commission Chairman William Welch has said that the clause was inserted to close a loophole that has existed since the county lost a discrimination case in 1981.