A cop on his dinner break caught two men in the act of stealing $55,000 from Upper West Side ATMs, cops said.

Officer Juan Rodriguez was at the Beacon Theatre at 74th and Broadway at 9:45 p.m. Friday when he saw Sivaruban Gnanapandithan, 28, and Ragavan Pathmasen, 24, both of Canada, near a Chase Bank and noticed something “odd.”

“They were really casing the place,” said the eight-year NYPD veteran.

He saw them use a blank card with a white sticker to withdraw cash. When they did it again at a second bank, he busted them — and found that they had about $55,000 and multiple bogus ATM cards in their backpacks.

The charge was grand larceny.