A pasted FBG based cantilever beam accelerometer’s sensitization process method has been proposed in this paper. We have built the pasted FBG-based cantilever beam accelerometer’s sensitization process model. The sensor’s sensitivity was improved by adjusting glue thickness between FBG and cantilever beam. Theoretical model has been proved by ANSYS simulation and experimental analysis: Simulation analysis shows that when distance between fiber core and cantilever beam is greater than 0.4 mm, it can be used to enhance sensitivity. Experimental analysis shows that when distance between fiber core and cantilever beam is 1 mm, sensitivity of sensor is increased by 2.9 times compared with the conventional process, but it has no effect on the sensor dynamic characteristics. Compared with conventional sensitization method, it’s more general, and can be applied to all pasted FBG accelerometer for enhancing sensitivity.