This paper introduces the design and key technology of a high-speed data acquisition and processing system based on DSP. The system realizes high-speed data acquisition of 40 Msps by high-speed A/D and CPLD, and sent the data to DSP for processing. It can realize the functions of DC removal, parameter measurement, digital filter, signal sampling and interpolation, spectrum analysis. Through key operation, the system display processed waveform and parameters with LCD screen, and can display data acquisition waveform, phase spectrum, and power spectrum. The test results of system show that the system has realized the anticipated goal of study. The system can be further developed as a high speed multi function virtual instrument. The research results have certain reference significance for the follow-up research work. The man-machine interface is friendly and the operation is simple.