Starting from the principles and characteristics of fiber Bragg grating(FBG), the possibility to monitor the ice on power transmission line by using FBG sensors was experimentally and theoretically analyzed. The one-side and two-side simple supported beams were established, the relation between reflected wavelength of FBG and the loading on beams was studied. Then the experimental data was fitted by using least squares and thus the mathematical relation between wavelength offset and the loading on beams were obtained. The result shows that it is practical to monitor the weight of ice on power transmission line by FBG sensors.