An 18-year-old man was charged with stabbing an off-duty police officer and slashing another man after he crashed a party at the cop’s East Elmhurst home over the weekend, police said on Sunday.

Diego Valesco drunkenly wandered into the home by the corner of 30th Avenue and 94th Street about 9:30 p.m. on Saturday, authorities said.

But when Valesco was being escorted out of the house by the 43-year-old officer, he lashed out, stabbing the off-duty cop in the arm and slashing a 59-year-old man, police said.

advertisement | advertise on newsday

Valesco, who lives in Jamaica, was charged with two counts of felony assault.

The officer and the other man were taken to New York-Presbyterian Hospital Queens, where the officer was treated and released, police said.