Through analyzing the failure mechanics of rock under blasting effect, the optical fiber sensing system was used to monitor the strain of surrounding rock under blasting effect. Combined with practical exploration, the stability of surrounding rock was computed by numerical simulation using the blasting wave obtained from the site. According to the change regularities of displacement, stress, acceleration, and velocity of tunnels before and after explosion, the layout of key monitoring points was optimized. When disposed the monitoring position of sensors, the regular points should be considered to use as key points and the periodical monitor should be a part of the long-term monitor. In practical application, considering the geology condition in site, monitor points should be added on the area with joints and faults to assure the integrity of monitor data and the preciseness of decision.