A man robbed an 11-year-old boy on a Brooklyn street last Thursday and whacked the youngster with a cane when he tried to retrieve his cell phone, police said.

The theft took place about 6:40 a.m. near 50th Street and 5th Avenue in Sunset Park, cops said.

After the robbery, the suspect fled north on 4th Avenue, according to police.

Surveillance footage provided by police shows the suspected crook calmly walking with the aid of his walking stick.

He is described by cops as light-skinned, and was last seen wearing a gray hoodie, blue and black jacket and blue jeans.