Abstract: The structure of multi-channel arbitrary waveform generator(AWG) is analyzed,the methods for adjusting phase difference between output signals are discussed,and then the resolution and range of each adjusting method are obtained. For the error produced by clock skew and channel delay in the design,a method of multi-channel AWG with phase calibration module embedded is presented.The advantages and disadvantages of two correlation algorithms in measuring phase difference are discussed.The correlation algorithm is carried after sampling two signals simultaneously for measuring phase difference.Then,the experiments about controlling phase difference are conducted,and the results show that the method is feasible.