In recent years,tilted fiber Bragg gratings have attracted much attention as a kind of particular structure fiber Bragg gratings.Based on mode coupling theory,the effect of grating period on transmission spectrum of tilted fiber Bragg grating(TFBG)were investigated by means of simulation method.The results show that the shift of wavelength displays a good linear relationship with period.The conclusion is very useful in improving the sensitivity and measurement accuracy in strain measurement.In addition,a single fiber could be used to measure multiple sets of data.