Voltage tunable metamaterial of short cross type array based on liquid crystal (LC) is proposed to achieve phase compensation at U-band frequencies. Simulation results show, by increasing bias voltage from 0 to 14 V, the metamaterial presents 250° phase compensation at 52 GHz. Moreover, the resonant frequency is continuously and reversibly shifted from 53.6 GHz to 49.9 GHz. By adjusting the permittivity of the LC excitation region of the metamaterial to change the resonance characteristic of the array unit, phase compensation is achieved, which provides a new method for the design of the planar reflect array antenna.