The present disclosure provides a power mixer having high-linearity transconductance, a transmitter and an RF transceiver. The power mixer having high-linearity transconductance comprises a power mixer and the following circuit structure: a mixer switching circuit having an output terminal directly connected to an input terminal of the power mixer; and a transconductance amplifier having an input terminal connected to an input terminal of the mixer switching circuit, wherein the output terminal of the mixer switching circuit supplies a current to the power mixer based on a voltage received by the transconductance amplifier from the input terminal of the mixer switching circuit.