Abstract: Aim To manufacture a kind of digital sinusoidal signal generator with the better structure and electric performance. Methods All kinds of the high precision digital signals such as step, uniform, sinusoidal, period uniform signal and so on were generated by 8098 single chip processor with the software method, then the digital to synchro converters (DSC) were used to convert the digital signal into the three phase analogous voltage output of the synchro which is needed by the servo system. Results The shortcomings in the structure and the electric performance of the mechano electronic sinusoidal signal generator have been successfully overcome by this new type of multifunctional digital sinusoidal signal generator. Conclusion The results of the laboratory experiments and the real system tests show that the generator presented in this paper, which has the simple structure, light weight and small volume, can completely meet the needs of the debugging of the servo system, and it is reliable and has the promising applicable prospect.