A board connector assembly has a receptacle connector and a plug connector. The receptacle connector has a first insulative housing, two sets of first terminals and two first metal reinforcing members mounted respectively on two opposite ends of the first insulative housing. The plug connector is detachably engaged with the receptacle connector and has a second insulative housing, two sets of second terminals and two second metal reinforcing members mounted respectively on two opposite ends of the second insulative housing. The first and second metal reinforcing members enhance structural strength and durability of the receptacle connector and the plug connector.