Bosses at a Brooklyn-based Jewish nonprofit allegedly fired a nonreligious employee for refusing to wear a yarmulke, the former staffer claims in a federal suit.

Avraham Hartman, who was born to a Jewish family in Israel, says supervisors told him to wear the cap after he was hired at HASC Center, with one arguing that Hartman was Jewish because his mother was.

After he refused, that supervisor repeatedly asked, “Do you need a vacation?” the suit alleges.

Hartman, 26, “does not practice any specific religion,” said his lawyer, Abraham Melamed. The center, which helps the disabled, declined to comment.