The invention belongs to an RF wireless receiver integration circuit technical field, in particular to an orthogonal down-frequency mixer with low power loss and high performance. The invention consists of an RF conversion transformer, an LO switch class, an IF load class and a power supply bias; wherein, the RF conversion transformer amplifies and transmits the received RF current signals; the orthogonal LO switch class leads the RF current signals to be alternatively output on an output differential load by a LO frequency with the phase difference of 90 DEG, thus implementing that the RF frequency multiplied by the orthogonal LO frequency obtains the orthogonal IF signal which is then output on the load. Compared with traditional Kilbert frequency mixers, the circuit structure replaces the differential transistor of RF amplification class by an on-chip integration amplifier, which can lead the frequency mixer to be applicable to low power voltage and dramatically reduce circuit noise and signal distortion; two orthogonal LO switch classes are combined into one circuit, which leads the frequency mixer to output orthogonal IF signals, simplifies the design of the wireless receiver and obviously reduces the power loss of the frequency mixer module.