The girls reported that a man, driving a white van, called them over and asked them to get inside.
It happened at a play park on the Lismenary Road on Saturday at about 11:00 BST.
A male passer-by asked the man what was going on and he drove off in the direction of the nearby Larne Line.
The driver of the van was described as being about 40 years old and was wearing a black baseball cap.
Police are investigating a suspicious approach on two young girls in Newtownabbey.