This paper introduces a kind of Fiber Bragg Grating(FBG) pressure sensor.The FBG is bonded to the self-designed open-loop plexiglass to form a FBG sensor.The relation expression between the FBG wavelength shift and the pressure is given.The experimental results show that the sensor shows a good linearity in the range of measured pressure and the FBG pressure sensitivity coefficient reaches 0.162 nm /N
basically in agreement with the theoretical value.