In order to improve the detecting efficiency of the Hall vehicle speed sensor, an improved detection system was presented in this paper. This system was consists of five parts of system manager, A/D converter, D/A converter, voltage comparator, and a high-speed programmable counter array. The quality of Hall vehicle speed sensor online was evaluated, and the statistical result was graphically displayed by PC. Compared with the synchronous detection of digital storage oscilloscope, it is shown that the detecting accuracy of the system can then meet the requirements of industrial production, and will be suitable for mass production.