Radio frequency power amplifier

The invention relates to a radio frequency power amplifier. The radio frequency power amplifier comprises an on-chip transformer, and is characterized in that a primary coil of the on-chip transformer is formed by connecting two coils in parallel and is embedded among three coils of a secondary coil to increase the current capacity of the primary coil, enhance coupling with the secondary coil and improve the coupling efficiency; and for enabling time delays of a signal in the two primary shunt coils of the primary coil to be the same, the two primary shunt coils are crossly connected, namely the two shunt coils of the primary coil are respectively divided into two parts, and half of an inner coil is connected with half of an outer coil. According to the radio frequency power amplifier, the current of the transformer can be increased, and the required area of the transformer can be reduced, so that the area of chips is saved, and the problems of large volume, complicated processing process, low coupling efficiency and the like are solved.