Considering the bare optical fiber Bragg grating(FBG) being fragility,an Al box encapsulating technique for FBG temperature sensor was developed.The encapsulation was also in expectatio to minimize the strain sensibility of the encapsulated FBG temperature sensor.The temperature and strain sensing characteristics of the encapsulated FBG and the bare FBG were theoretically and experimentally studied.The experimental comparison results of encapsulated FBG and bare FBG indicated that the strain sensing property of FBG was much less than bare FBG,and the temperature sensing property of encapsulated FBG was 1.8 times as much as that of bare FBG.