This paper describes the experimental results of a small size pulse tube cryocooler (PTC) with three types of phase shifters. The phase shifter plays a key role in the cooling performance of the PTCs. The basic, orifice and double inlet phase shifters have been tested. In particular, we take notice of temperature at the cold end, and pressure at the hot-end of regenerator and pulse tube. The inner diameter and length of pulse tube are 14 mm∅ and 22 cm, respectively. Copper screens (200 mesh) of diameter of 18 mm were filled in the regenerator as a regenerator material. The PTC is operated at 4.5 Hz with an air cooled compressor of 800 W. Attained temperature at the cold end of basic, orifice and double inlet phase shifters were 205.6, 133.7 and 84.5 K, respectively. The characteristics pressure wave curves were observed in each phase shifter.