Abstract: A new voltage tuned Doherty power amplifier (DPA) with both high efficiency and good linearity for mobile basestation is presented in the paper. The power division ratio between the carrier amplifier and the peaking amplifier of the DPA is voltage tunable, so is the synthesized output phase, thus assuring the best power division ratio and the best synthesized output phase, combined with the internal linearization techniques, the best JP2performance of DPA could be achieved. A quiescent bias circuit is designed for the DPA to assure the stability, which makes a less than 5% fluctuation of the bias current of the amplifier during the high and low temperature experiment form -25 degrees to +50 degrees. The working frequency of the power amplifier is from 870MHz to 890MHz, with the gain larger than 58dB. The tested ACLR is better than -47.5dBc at 50.06dBm output power under CDMA2000 test; while the overall efficiency is 42.3% (include the driving stage).