The sense,priciple and method of using the fiber Bragg grating for dynamic strain measurement are described in this paper. Two methods of using the fiber Bragg grating for wavelength shift demodulation are proposed when it is employed in the dynamic strain measurement. One is based on the fiber Mach Zehnder interferometry which is the dynamic phase demodulation suitable for high frequency bandwidth dynamic sensing and measurement and the other is the direct detection of the Bragg wavelength by DWDM with limited frequency bandwidth or medium frequency responding.