A card edge connector includes a first insulator, a second insulator, first terminals, second terminals, and a circuit transferring board. The first insulator has a plug space, first terminal holes, and second terminal holes. The second insulator abuts against the first insulator and has first slotted holes, second slotted holes, and a slot. The first terminals are disposed within the first terminal holes and the first slotted holes, and the second terminals are disposed within the second terminal holes and the second slotted holes. The circuit transferring board is inserted into the slot. The circuit transferring board has first conductive portions and second conductive portions, where back contact portions of the first and second terminals are electrically coupled to the first and second conductive portions, thereby solving a problem of a conventional welded connection. The present invent also provides a card edge connector assembly.