To research the dynamics characteristics of the belt conveyor in actual working condition,by using the new method to establish the dynamics equation of the belt conveyor,that is through the "flexible beam and belt unit" to establish the mechanics equation,the coefficient matrix is derived.By using the RecurDyn software,the rigid-flexible coupling model of machine is built and according to coefficient matrix,the dynamics analysis is carried out,the dynamic characteristics of the conveying belt is obtained,it shows the conclusion that according to the conditions set by the different conditions of the belt conveyor,the method by using the rigid-flexible coupling simulation analysis is more close to the actual working condition.The correctness and advancement of the rigid-flexible coupling dynamics simulation analysis method are verified.A more effective and closer to the actual method of analysis for improving the system stability and structure optimize is provided.