The temperature response and sensitivity enhancing technology concerning fiber Bragg grating (FBG) is analyzed. A special kind of heat-resistant polymer is used to coat FBG to enhance the temperature sensitivity of FBG sensor. The polymer coating and solidifying process of FBG is improved. A kind of heat-conducted adhesive is used to reduce the friction between tube and polymer, and eliminate the chirp effect of FBG caused by the asymmetric shrinkage of polymer during the package process. The experimental results show that the FBG sensor can measure temperature from 20 ℃ to 180 ℃. The temperature response sensitivity is 0.05 nm/℃ from 20 ℃ to 130 ℃ and 0.22 nm/℃ from 130 ℃ to 180 ℃, respectively, and the response trend line has good linearity in both areas. This kind of sensor is easy to fabricate and can be used for high temperature measurement.