Because of the adaptability of mechanical control,a cantilever which is coupled with a bourdon tube is proposed.Fiber Bragg grating(FBG) is affixed on the surface of the cantilever,and the affixing direction is consistent with axes of the cantilever,so an optical fiber pressure sensor is gotten.The relations of central wavelength shift and the pressure are analyzed.It is indicates that the central wavelength of the sensor and the pressure has good linearity.The pressure applied on the cantilever can be measured by measuring the central wavelength.The experimental value of the pressure sensitivity coefficient is 0.436 5 nm/MPa.It is 142 times of that of the bare FBG.It is also indicated that the pressure sensitivity of the sensor varies with the size of the cantilever and bourdon tube.