Abstract: In view of the difficulties in the field program upgrade of mine sensors in underground coal mines, a remote program update method based on CAN bus and IAP function is designed to get rid of the dependence of embedded software upgrade on the programmer. By designing the Flash programming method and program starting and guiding mode of STM32F103 microprocessor, the on-line upgrade of mine sensors in underground coal mine is realized. This paper introduces the overall implementation framework, upgrades program structure and process, and elaborates the IAP program update principle. The mine bus sensor program can be updated online by field application verification.