In this paper, based on the quantitative stereology theory, the quantitative characteristics of particle group such as particle size distribution, roundness were determined by using Quantimet 600 Image Analysis. The experiment parameters of quantitative stereology theory such as minimum samples, grey threshold were also studied in this paper. The experiment results show that the characteristics of 3 D microstructure can be precisely obtained by using the theory of quantitative stereology and the method of image analysis, and the results have higher reliability.