A battery connector includes an insulative housing and a plurality of terminals retained in the housing. The housing defines a mating surface, a rear surface opposite to the mating surface and a plurality of passageways penetrating through the mating surface and the rear surface along a front-to-back direction. At least one pair of first grooves is formed in opposite inner sidewalls of each passageway and running through the rear surface. A pair of slits communicates and is staggered with the corresponding first grooves along a vertical direction perpendicular to the front-to-back direction. Each terminal includes a retention portion with at least one pair of barbs defined at two sides thereof. The retention portions pass through the first grooves along the front-to-back direction and are pressed along the vertical direction so as to retain the barbs in the corresponding slits.