Differential absorption method is an important method for methane remote monitoring. Based on the methane absorption spectrum in near-infrared region, a novel kind of fiber remote sensing system utilizing fiber Bragg grating (FBG) filters and 1.31 μm superradiance light-emitting diode (SLED) was developed for real time absorption measurement. The highly sensitive technique was achieved employing the two-wavelength differential absorption method. FBG has low insert loss and can be produced easily compared with dielectric interference filters. This system has a number of advantages such as all-fiber sensor, high sensibility, simply construct and long-distance measurement. The measurement sensitivity is 0.1％. It is 2% of the lower explosion limit of methane density in air.