Abstract: Arbitrary waveform generator (AWG) is a instrument which can generate arbitrary excitation signal. Output bandwidth, the number of channels and synchronous accuracy between different channels are the key specifications of AWG. In order to achieve high bandwidth, a multi-memories parallel structure is proposed to break through operation speed limitation of phase accumulator and look-up table. However, this structure introduces more complex synchronous error than traditional structures. The synchronization requirements of AWG with multi-memories parallel is analyzed emphatically in this article. The random initial phase of data clock and random trigger position are eliminated by deliberate distributing clock and trigger signal. The design of embedded phase calibration module is used to eliminate the random phase difference. Finally, the specifications of AWG are verified.