Monitoring method for dynamical stress of centrifugal blower vane based on Fiber Bragg Grating (FBG) sensing technique is presented in this paper. Consisting of FBG sensors, FBG interrogator and fiber optic rotary joint, this monitoring system has bare FBG as strain sensor, monitors stresses at the inlet and outlet of the centrifugal blower. Details about stick up method of FBG sensors are shown in this paper, either. In addition, this method has been applied to experimental model of centrifugal blower, and it was found that: stress at the outlet of the air vane is more than that at the inlet; within the working range, stress of air vane increases in company with increment of rotating speed, though it is not linear relation between them.