Madonna’s boyfriend insists he didn’t cheat on her — because his mother was watching him, reports.

Jesus Luz has blasted reports he kissed lingerie model Luciana Costa, 31, at a party in his native Brazil earlier this month.

“I danced with her, but I danced with everyone at the party,” he said. “My mother was at my side at the party and never would I become intimate with a woman if my mother was nearby — even if I was interested in that person.”