Abstract: Since the error of the result is comparatively large in the linear filtering demodulation with the quasi-linear waveband of LPFG when fitting the quasilinear waveband of long period fiber grating(LPFG) only once, through fitting the quasi-linear waveband of LPFG in several sub-wavebands and controlling the temperature of the LPFG were introduced so as to cause the shift of the resonant wavelength of the LPFG to realize demodulation with different sensibility. The implementation based on DSP was given, the monitoring interface realized by MFC programming based on the dialog box of the VC++ was given, and the potential application areas were given as well.