Two phony utility workers robbed an elderly Brooklyn woman after she let them into her house, cops said.

The two men knocked on the 88-year-old woman’s door at her Manhattan Beach home on Oct. 18 claiming to be utility workers, authorities said. One of the men was wearing a yellow construction vest during the scam, police said.

Once inside, the men immediately demanded money, grabbing $2,500 in cash, cops said.

They drove off in a dark-colored pick-up truck with third man, authorities said.

The woman refused medical attention after the robbery. The robbers, who have not been arrested, were last seen driving away from the home near the intersection of Oriental Boulevard and Ocean Avenue.