In order to overcome the large size and high price of the traditional arrayed wave-guide grating demodulation system, a demodulation scheme using a narrow-band light source as the input light source and adopting a combination of edge filter and arrayed wave-guide grating was proposed to realize the temperature demodulation experiment of fiber grating temperature sensor after packaging. Using the narrow-band light source as input, the edge filter method made the central wavelength shift of temperature sensor reflection spectrum correspond to the change in the output light intensity of demodulation optical path. The wavelength division multiplexing of arrayed wave-guide grating was used to realize the simultaneous measurement of multiple sensors, and the distributed measurement with multi-sensor and multi-channel was performed. The experimental results show that the wavelength demodulation range of the demodulation system is 1 545.30 nm~1 560.50 nm, the temperature range of 35 ℃~42 ℃ was detected, and the wavelength demodulation accuracy is ±5.34 pm. The temperature measurement error can reach to ±0.1 ℃.