This paper proposes a compact and tunable phase shifter based on Schiffman topology for beam steering antenna in Ku band. The achievement of the tunability is carried out by placing capacitors on the phase shifter to control the phase shift variation. For this, two configurations have been developed and optimized with ADS software simulator, the first used two capacitors and the second used three capacitors. By adjusting the capacitances, the phase shifters provides a continuously tunable phase shift of 70.66° and 94.4° at 12.7 GHz in two and three compensated capacitors structure, respectively. The phase shifter compensated with two and three capacitances is able to achieve a beam steering angle of 14° and 20°, respectively. Simulations results show a good performance with excellent phase shift characteristics over a wide bandwidth.