Abstract: As a key component of coal plough,traction block has a significant impact on the work efficiency and dy- namic reliability of coal plough. Based on the coupled multi-body system dynamics theory,the coal plough’ s flexible virtual prototype coupling model of plow bit and traction block was established in this study. Combined with the actual working conditions,plow bit and plough chain’s load files were obtained based on the “coal plough design system soft- ware”. The equivalent stress and strain contours of the traction block were obtained using ADAMS. Also,the traction block’ fatigue life analysis was conducted using NSOFT. In addition,the optimal design in 12 areas of low fatigue life were performed. After the optimal design,the traction block’s maximum equivalent stress and strain were reduced by 46. 4% and 48% respectively,and the lowest fatigue life was increased by 184. 35% ,which met the design require- ments.