Based on the principle of the displacement amplification of the moire，and under the circumstance of constant grating pitch when the angle is very small，between the gate lines is proportional inversely to the width of the moire，Young's modulus of the steel wire is measured. Then，through the analysis of the measured data and calculated results，we have reached a conclusion: the width of the moire decreases with the increase of the angle;the measurement deviation increases as the moire grating angle increases，but less than 5%. Finally，the experimental and theoretical values are compared to determine the feasibility of the methodology of moire fringe measuring Young s modulus