A novel fiber Bragg grating sensor for high pressure is proposed. The relationship between the central wavelength of FBG and the pressure is deduced,and the analytical formula of pressure sensitivity is also derived. From the result of ex periment,the pressure sensitivity is derived,which is 19.73 times than that of the bare FBG. From 0 MPa to 45 MPa,the fi-her Bragg grating sensor has good linearity and repetition,the experimental results agree with the theoretical one. It is also indicated that the pressure sensitivity and range of measure are tunable.