The Virginia House of Delegates approved legislation today that reverses a two-year-old court ruling that rendered the Arlington Fair Housing Board powerless to enforce the county's antidiscrimination laws.

The measure, which had been introduced at the request of the Arlington County Board, specifically grants the agency most of the powers it lost when a state judge ruled it lacked authority to hold public hearings, reach findings and issue corrective orders. The bill, which now goes to the state Senate, was approved without debate on a 77-to-17 vote, although several Republicans said later they objected to it.

In a case growing out of a complaint filed by a Vietnamese couple against an apartment complex, Arlington Circuit Court Judge William L. Winston had ruled that the agency lacked enabling legislation for its acts. The ruling was upheld by the Virginia Supreme Court last summer.

Agencies such as the Arlington Fair Housing Board have long contended that they are better equipped to resolve discrimination complaints than the courts, because the time and expense of filing a law suit frequently discourages persons suffering from discrimination.

Candace Tapscott, executive director of the housing board, said her agency received a total of 50 complaints last year, about half of them coming from the county's growing Asian-American population. Most are resolved by conciliation, she said.