A MCU control high-precision portable dual-channels DDS arbitrary waveform generator has been developed.FPGA used as core, TFT for graphic and menu-interface,USB1.1 & Delphi7.0 were used for connecting with upper computer and graphical user interface(GUI).Clock piece wise-frequency division method was used in low frequency band.It can generate common waveforms,such as ±8V voltage sine wave with frequency from 0.01 Hz to 10 MHz, as well as data-VHS bit-stream output, modulation signals, random noise, sweeping signals, and user-defined time or frequency domain waveform can also be generated. Signal parameters can be adjusted step-by-step in-system. Experiments showed that the design was effect. Along with introduction of the system design ideas, this paper focuses on methods of FPGA design, signal input and improvement of time domain precisions of low frequency band.