Abstract: In order to study noise and vibration characteristics of shearer under complicated coal seam occurrence conditions, vibration and noise sources of shearer were analyzed , and conclusions were found: noise of shearer is formed by coupling of different forms of noise, and the vibration caused by the nonlinear instantaneous impact load on the cutting tooth during cutting process is the main source of noise generated by shearer, improving equipment vibration in working process of shearer can effectively reduce noise level of working face. The virtual prototype of shearer cutting unit was established by using co-simulation technology, and the vibration and deformation of key parts were obtained by dynamic simulation analysis: the vibration of the protruding end and the heightening ear of the shell are more violent which seriously affects stability of the drive system and the height adjustment system; the serious distortion and violent vibration of the planetary frame reduce life of axial bearing. In order to reduce vibration of shearer in working process, the shell structure was optimized according to the simulation results. The vibration of the optimized shell is obviously weakened and the mechanical properties are significantly improved. The vibration characteristics of shearer can be effectively improved, the noise level of the working face can be reduced, and the shearer can operate effectively and smoothly.