A toy rocket launching device includes a stand and a positioning unit is pivotably connected to the stand. A control unit includes a control member which has a first end connected to an injection nozzle of the rocket and a second end of the control member extends through a positioning unit and is secured by a threaded sleeve. An valve is inserted into the first end of the control member and a cap is mounted on the first end of the control member. An activation member is located in the positioning unit and multiple balance cables are connected between the activation member and the cap. An end of an activation cable is connected to a center of the activation member so that when the activation cable is pulled, the cap is simultaneously pulled to activate the injection nozzle to lunch the toy rocket.