As a non-contact measurement method,the vision-linear structured light’s combination measurement technology is very great significant in the track detection.In order to solve the problems of complex structure and difficult image processing of the conventional track detection equipment,a more simple and effective detection system is designed in this paper.Based on the theory of track detection of vision-structured light system,the 3D measurement method of structured light system,the unification of structured light models on different tracks’ directions,the method of line processing and rail gauge calculation are introduced.The relevant parameters of the detection system were obtained through experiments.80 sets of gauge measurement data showed that,the system’s maximum error is 0.96 mm,the root mean square error is 0.56 mm,and the measurement accuracy reaches the millimeter level.So,the system can meet the requirement of general track detection effectively.