Abstract: This paper proposed a method to enhance the sensitivity and the resolving power of the space object-s temperature measurement through optimizing the waveband. We built the mathematical model for measuring the temperature, in terms of the signal-to-noise ratio(SNR) and the relationship among the relative temperature measurement sensitivity, the temperature resolving power，the linearity of the metrical curve and the working waveband, and optimized the central wavelength and the bandwidth. The optimal results show that the wavebands fit for measuring is 8.0 m ~9.6 m, the bandwidth is 60 nm, the biggest resolving power of the measurement temperature is 0.06 K, and an SNR above than 5 is achieved. The proposed method improves the resolving power of temperature measurement and the measurement sensitivity of the system by 8.7% and 11.3% respectively.