A double-locking connector including a front holder for double locking terminals within a connector housing where the terminals can be removed from the housing without disengaging the front holder from the housing. The double-locking connector includes a connector housing including terminal accommodating chambers which have stoppers against which metal terminals abut when they are inserted into the terminal accommodating chambers from the rear, and flexible locking pieces adapted to lock the metal terminals in the terminal accommodating chambers, respectively. The connector also includes a front holder which is engageable with the connector housing from the front. The front holder has flexible locking pieces which are respectively engageable with the metal terminals. Each of the flexible locking pieces has temporary locking protrusions and final locking protrusions which are engaged with locking portions forming the front end of the respective terminal accommodating chamber. When the front holder is in a temporarily locked position, the flexible locking pieces are not engaged with the metal terminals; when the front holder is in a completely locked position the flexible locking pieces are engaged with the metal terminals; and when the front holder is thereafter moved in a perpendicular direction the final locking protrusions become disengaged with the metal terminals.