The shafting precision of the inertial stabilized platform has direct influence on the technical index of electro-optical reconnaissance system.A method was proposed for improving the shafting precision of inertial stabilized platform by using the steel belt transmission technique.Based on the belt transmission characteristics,analysis was made to the working principle,implementing methods,accuracy analysis, simulation and calculation of the steel belt transmission technology.The key points and result of design was presented,and experimental verification was carried out.The result showed that:the belt transmission mechanism is stable,reliable,and accurate in operation,which can satisfy the stabilization accuracy requirement of products.