A high precision amplitude and phase modulation mechanism(APMM) with the advantages of high reliability, high linear amplitude and phase characteristics and fast design is described in this paper. Through the cascading test, the consistency of the phase difference between channels of any multi channel module is ±1°, the amplitude consistency between any functional units is less than ±1 dB, the phase consistency is ±1.5°, the absolute delay accuracy of any functional unit is ±1.5 ps, and the amplitude flatness of multiple frequency relative bandwidths is ±1 dB. This APMM can be applied to any electronic system，any channelized design，any functional circuit or chip design. Through a large number of engineering applications, it has been confirmed that the scheme has effectively and reliably improved the amplitude and phase characteristics of various RF systems or modules.