Abstract: In order to quantitatively study the dynamic characteristics of belt conveyor during starting and braking，the characteristics of the viscoelastic model of conveyer belt were analyzed by fractal dimension-based evaluation method.The discrete finite element model and the simulation model were established.The sinusoidal speed control curve of belt conveyor system was designed.The characteristics of longitudinal dynamic tension of nose part and rear part of belt conveyor during starting and braking were studied.The fractal theory was applied to analyze the relationship between the tension force dimension of the head and the stability of conveyor system at different starting times,and the dynamic characteristics of the built-in tensioner and the external tensioning device.The results show that the fractal dimension is suitable for evaluating the dynamic characteristics of the belt conveyor.When the fractal dimension increases,the stability of the system becomes worse and the failure rate of belt conveyor becomes higher.When starting,the tensioning dimension of the head part is larger than that of rear part of engine,the head part is more prone to failure,and the built-in tension device has larger load dimension and higher failure rate.When starting time is 35～40 s,the tension dimension of the head part is small,and the belt conveyor has high stability.