A multi-channel optical fiber Fabry-Perot (F-P) sensing demodulation system based on light emitting diode (LED) pulse demodulation and optical fiber array is proposed. Based on multi-channel optical path difference distribution theory model, multi- channel parallel light path is realized with optical fiber array and LED pulse demodulation is used for channel switching, which alleivates the temperature rising of positive- negative (PN) junction and the influence of the PN′s rising temperature on demodulation. The experiments investigate the effects of pulse duty cycle and modulation frequency. The results show that the demodulation can be in good perfermance when duty cycle is less than 60% and the modulation frequency is higher than 35 Hz. Using pulse modulation with 50 Hz and 12.5% duty cycle, the experiment results show that the 8-channel system has good channel consistency, and the modulation precisions of all 8 channels are less than 0.045% in full scale(F.S.).