In this paper, we present single-pole double-throw (SPDT) switch at Ka-band for phased array front-end applications. The proposed switch composed of three shunt arms and a quarter-wave length impedance transformer in series on each branch. The stacked-FET configuration was adopted to enhance the power handling capability. Implemented with 0.15um GaAs pHEMT technology by WIN Semiconductor, the overall chip size was 2 mm by 1 mm. The measured insertion loss was less than 3 dB with better than 25 dB isolation from 15 GHz to 35 GHz. The proposed configuration also featured an input 1-dB compression point of 26 dBm.