A USB connector includes an electrically insulative housing, which has an exposed space area defined in the bottom wall of a tongue plate at the front side of an upper base member thereof and terminal grooves formed in the bottom wall of the tongue plate, first metal terminals embedded in the upper base member and the tongue plate each having a contact end positioned in a respective locating groove in the exposed space area and a bonding end extended out of the upper base member for bonding, and second metal terminals each having a base portion respectively upwardly forced into the terminal grooves in direction perpendicular to the insertion direction of a matching plug and a front contact end suspending outside the terminal grooves and a rear bonding end extended out of the rear side of the upper base member for bonding.