A trigger activating tactical light grip includes a Picatinny rail mount to assemble the grip to the firearm, a tactical light mount to mount the tactical light and a grip to provide a place for holding the gun. In the grip, there is a trigger to initiate movement for a connecting rod, and the connecting rod is to deliver the movement of the trigger, a tunnel for the connecting rod to slide along, a circular shaft to assemble the trigger, and a fixing pin to keep the connecting rod to be contacted with the tactical light switch. When a user provides pressure with a finger on the trigger, it pivots on the circular shaft and leads the connecting rod to slide along the tunnel. As a result, the connecting rod exerts pressure to the switch of the tactical light and then the aim of activating the tactical light is accomplished.