An ex-cop’s craving for a pricey rubber-chicken dinner could land him in the slammer.

Retired NYPD Detective Allen Caplan was busted for posing as the director of a city agency in a bid to score free entry to the $1,100-a-seat US Investment Management Awards dinner at the swanky Mandarin Oriental hotel, authorities said yesterday.

After a tip from organizers, an undercover cop busted 52-year-old Caplan at the event’s door and charged him with criminal impersonation and attempted grand larceny. He was arraigned yesterday and released without bail.