The invention discloses a differential power amplifier for a CMOS with the radio frequency of 0.1-1.2GHz. The differential power amplifier comprises an input blocking circuit, a drive stage polarization and input match circuit, a drive stage, an inter-stage blocking circuit, a power stage polarization and inter-stage match circuit, and a power stage and input blocking circuit. The drive stage provides drive gain and good input match. A power stage amplifying circuit provides power gain and good output match. The drive stage and the power stage amplifying circuit respectively comprise two NMOS tubes, two inductors, two current polarization circuits and two outer blocking capacitors. The power output stage comprises two feedback resistors and an inter-stage blocking capacitor. A common source structure is adopted, and the area of a chip is small. In the whole differential structure circuit, parameters of an adopted component can be determined after indexes of items such as the whole circuit gain, the bandwidth and the output power are integrated, and therefore the high gain, the high linearity and the high output power within 0.1-1.2GHz can be achieved.