The bus, which left Atlantic City at 10:00 a.m., was forced to pull over in Port Republic, New Jersey around 11:00 a.m.
A photo from inside the bus showed roaches crawling on the bus seats.
Other photos obtained by Action News show some of the 48 passengers waiting on the side of the road.
The Greyhound bus company said it sent another bus to pick up those passengers and bring them to New York.
"We apologize for this inconvenience and our team will be transporting the first bus back to our garage to investigate the situation and determine its cause," spokesperson Timothy Stokes said in a statement.