A ball bearing slide assembly includes a first slide, a second slide, a slide-aiding member, and a positioning member. The first slide is slidably received in the second slide. The second slide defines a receiving hole. The slide-aiding member is sandwiched between the first slide and the second slide. The slide-aiding member defines a slot. The positioning member is pivotably mounted to the slide-aiding member and forms a positioning tab. The positioning tab extends through the slot of the slide-aiding member for engaging in the receiving hole of the second slide to lock the slide-aiding member with the second slide such that the first slide is slidable inward relative to the second slide without pushing the slide-aiding member inward. The first slide, when slid inward, is capable of pushing the positioning member to disengage the positioning tab from the receiving hole such that the slide-aiding member is slidable relative to the first and second slides.