Abstract: We conduct a microwave spectrometer experiment to verify Scherrer equation.W e derive the equation without approximation to meet the requirement of our experiment.The model, using XRD method, is tested with the microwave spectrometer and the result is analyzed，we have found that it follows the rule indicated by the equation qualitatively.W e process the data with software and the result is in agreement well with the mathematic expression formulated by Scherrer equation.W e analyze the elror at last，promoting the understanding of Scherrer equation.The experiment verifies Scherrer equation and the viability of our model，enriches teaching content of microwave spectrometer experimental project and improves students’innovation in building physical mode1.

Key words: microwave spectrometer, Scherrer equation, grain size, diffraction peak width