A Queens car wash is the first in the city to be unionized.

Workers at Hi-Tek Car Wash & Lube in East Elmhurst, most of them immigrants, voted 21-5 Saturday to join the Retail, Wholesale and Department Store Union.

They “are risking their jobs . . . to fight for fair treatment and wages,’’ said union President Stuart Appelbaum.

The workers filed suit against Hi-Tek in July, alleging that they were being paid below minimum wage. The suit is pending.

Hi-Tek is now the first unionized car wash outside LA.

Its owner did not return calls for comment.