The invention discloses a liftable tower crane and a control method. The liftable tower crane comprises a supporting frame, a control chamber which is arranged on the supporting frame, a height adjusting device which is arranged in the supporting frame, a boom which is arranged on one side of the supporting frame, a balancing arm which is arranged on the other side of the supporting frame, a counterweight arranged on the balancing arm, and a cargo hoisting mechanism which is arranged on the boom, wherein the cargo hoisting mechanism comprises a ranging device and a hoisting hook; a cargo rackis arranged in the ranging device; the ranging device is fixedly connected to the hoisting hook. The liftable tower crane has the characteristic of intelligently adjusting the height of the tower crane.