Sitch filed the suit in Miami, claiming he struck a deal with a promotion company last year to make a total of 3 appearances at Vegas nightclubs Chateau and Gallery by June 30th. 

According to the lawsuit, the deal was “pay or play” — meaning Situation was to get paid the full amount … even if the club decided not to use him all three times.

Situation claims the club only called him in once before the deadline … and only paid him $30k. 

Now, the “Jersey Shore” star is suing the promotion company for the balance — $60,000 — insisting it hasn’t held up its end of the bargain.

Calls to the promotion company Diversified Entertainment were not returned.