Recently, ZWP grating diffraction imaging instrument has been applied in the research and teaching of bi-grating imaging effects by some universities. However, there are problems exposed in the use. The main problem is position location of bi-grating operation which hardly achieves the “Z” shape that is fit for imaging path, especially the diagonal direction deviation of the second grating when it is moving in the platform, which leads to measurement errors for the bi-grating diffraction imaging, and the experiment results are inaccurate. To the grating imaging instrument, the electronic control method has been studied, which is to control moving and rotation of gratings more easily and with high measurement accuracy. The new reform plan of the grating imaging instrument is done and tested, and the experiment results are compared with before reform undone.