Witnesses say they saw the child screaming while being beaten in the middle of the store.
At this point, detectives are say they are looking for a 'person of interest,' and want to question him.
"They observed him with a doubled-over belt in his hand repeatedly striking the child," said Lt. Ribello Berton of Whitehall Township Police.
Investigators say about 10 to 12 witnesses watched as a man beat a six or seven year old child. A woman, believed to be his wife, carried a baby.
Two customers called 911 while others tried to intervene. The woman allegedly told those customers they had no right to tell her husband what to do.
The family then took off in a car, described as a white 2013 Infiniti.
Police and Home Depot won't release surveillance video that apparently shows the man with a belt in his hand being confronted by witnesses at the front of the store.
Sources say the beating was not captured on tape, which began in the plumbing section of the store.
Police say this does cross the line of child abuse if the claims are true.