A new dynamic-strain interrogation system based on a fiber Bragg grating(FBG) triangular filter is proposed and experimentally demonstrated in this paper.Through a chirp in grating period and an apodization in index modulation,we fabricated a FBG triangular filter,and utilized this filter to demodulate the dynamic-strain signal of another wavelength-matched FBG sensor.By comparing with the results measured by a commercial strain-gauge,this system is proved to have a good performance in the measurement of dynamic strain.Since the system is compact and passive,it is able to be integrated as a portable demodulation module.