Traditional synchronous demodulation of MEMS (Micro-Electro-Mechanical System) gyroscope is based on phase relationship of drive and sense positions. This relationship depends on the work mode of gyro. Moreover,the phase jitter of drive displacement is large,which makes the phase alignment of demodulator hard. To solve these problems,a new demodulation method based on quadrature error alignment was proposed,which is independent on work mode of gyro. Demodulator reference was extracted from PLL (Phase-locked loop) output,which has low jitter. Phase shifter of sense channel was used to delay quadrature error by 90°,compared with the reference signal. Therefore,Coriolis signal and the reference were automatically in-phase,and successful demodulation was achieved. To demonstrate this method,drive-mode and sense-mode circuits were elaborately implemented,and several critical blocks were care fully de signed. The demodulation of MEMS gyro shows that the vibration oscillation is stable and the operation of sense channel is correct. The scale factor is 1.415 mV/(°·s),and the bias instability is 108°/h. Moreover,the measurement results verify the validity of the demodulation method,providing solid foundation for further research. The method is also applicable to other vibratory MEMS gyroscopes.