The accident happened around 10 a.m. on Route 287 South at milepost 66 in Mahwah, shutting down the highway for around 3 hours.
Officials say the pickup truck was towing a camper when somehow both vehicles overturned and separated.
The pick-up truck dangled over the side of the overpass, while the camper stretched across the highway.
It was not immediately known how the driver and passenger got out of the truck.
State Police identified the driver as Davaasuren Altantsetseg, 37, and her passenger as 22-year-old Narangua Altankhuyag.
A spokesperson for the circus said the two ladies make up an act called The Mongolian Angels.
He said both women are okay.
He said, according to the women, the camper fishtailed and caused them to lose control of the truck.
He said several other people from the circus were with women, but the circus has not been able to get a hold of them yet. They were part of a convoy of several other circus acts headed from Walden, New York to Virginia.
The performers were not injured, and they continued on their way to Dulles, Virginia in another vehicle.
The southbound lanes of the highway reopened around 1:00 p.m.