A homeless man who robbed and beat a mother in front of her 4-year-old son told cops he wouldn’t have punched her if she had just coughed up $10, according to Queens prosecutors.

Derrick Chirse, 57, was charged Wednesday in Queens Criminal Court in the attack on Taslima Mazumder, 35, in Ozone Park after she refused to turn over her purse.

Chirse was seen fleeing on surveillance video and tracked to a homeless shelter, where he was arrested on Tuesday, officials said.

He told cops, “I wish I never did it. If she would’ve given me the 10 bucks, I wouldn’t have punched her,” prosecutors said.

Chirse was charged with robbery, assault, criminal possession of a weapon and endangering the welfare of a child. He was held on $100,000 bail.