It happened at 9:45 p.m. Saturday when the outdoor temperature was above 88 degrees.
Police say a woman walking across the parking lot heard a baby crying inside a locked gray Lexus parked outside the casino. She called 911.
Arriving officers forced their way into the car to retrieve the child.
As they were trying to locate a parent, 44-year-old Danny Ngo of Adams Avenue in Philadelphia came out of the casino.
Police say he had been in the casino for about 40 minutes.
Ngo was arrested and charged with recklessly endangering another person and endangering the welfare of children.
He was sent to Bucks County prison in lieu of 10 percent of $100,000 bail.