A novel displacement and temperature fiber Bragg grating(FBG) sensor based on cantilever structure is presented, and studied both theoretically and experimentally in this paper. FBG is affixed on the adjoiner between the cantilever and a fixed placode. Vertical displacement of the cantilever free end is measured by wavelength shift of FBG due to the strain action inflicted on FBG by the cantilever. The FBG section attached on cantilever is of different sensitivities to strain and temperature from that attached on the placode due to their making from different materials. Due to the spectral resolution of 0.1nm for spectral analyzer, the resolutions of displacement measurement and temperature measurement are 0.08mm and 3.1℃, respectively (the latter, with a constant displacement, might be 0.73℃), the measurement range of displacement is 10.5 mm.