The invention relates to an electrical connector assembly comprising a first connector and a second connector. The first connector comprises a first insulating body and first terminals. The first insulating body comprises an inserting wall. The first terminal comprises a U-shaped segment fixed to the inserting wall and a first soldering foot. Two outer surfaces of the U-shaped segment respectively comprise a coupling part. The second connector comprises a second insulating body and second terminals. The second insulating body comprises a receiving trough, separating plates, and separating troughs. The receiving trough matches the inserting wall. The separating plate comprises a first chamfer and a second chamfer. The second terminal comprises a pair of elastic arms, a main arm, and a second soldering foot. The pair of elastic arms is fixed in the receiving trough and matches the U-shaped segment. The main arm is disposed in the separating trough.