A labor union representing Prince William County school administrators filed suit against the county school board and others yesterday in an effort to force the board to consult with the union on personnel and other matters.

The suit was filed in federal court in Alexandria by the Prince William Association of School Administrators and Supervisors. The union claims the school board refuses to recognize its existence, denies it use of school facilities for meetings and denies members permission to attend union meetings without losing pay or vacation time.

The suit seeks an injunction and a finding by the court that the board acted illegally in refusing to recognize the union.

The Virginia Supreme Court ruled unanimously in 1977 that local governments have no power to bargain with their employes or negotiate labor contracts with them. Although the suit does not challenge that ruling or ask that the court force the board to negotiate with the union, a ruling on behalf of the union would be taken as a victory by prounion groups, several lawyers said.

William L. Helton, the Prince William County school superintendent and a defendant in the case, denied the allegations.Helton said the real issue was what he saw as a "conflict of interest in which administrators belonging to one union supervise other school employes who belong to other unions."

Other organizations in Prince William that represent school employes include the Prince William Education Association, representing teachers, and the American Federation of State, County, and Municipal Employees, AFL-CIO, representing service and maintenance staff.

According to the suit, the board has been willing to confer with these groups, but last year changed its policy to specifically exclude "any organization of administrators affiliated with a labor union.

The suit claims the school administrators are denied their constitutional right to free speech and due process by the board's policy.

Prince William County has 35,000 students and 2,000 teachers and administrators.

No trial date has been set.