Abstract: In this paper, the design,manufacture and test of a millimeter-wave reflected RF- MEMS 0/π phase shifter has been described. The test results show good agreement between design and test. Between 35GHz-38GHz frequency range, VSWR less than 1.8. The Insertion Loss is 3.5 ± 1. OdB when the phase shifter is on reference state and 2.0 ±0. 6dB when phase shift state. The phase shift is 180°±6° . The dimension of chip： 2.6mm ×2. 1mm ×0. 2mm.