Similarity of material is a key factor for geomecha nical model experiment. In this paper a lot of tests were made according to similar criteria and the study results of other experts. The model material can accurately simulate rock features at the site of Jingping Project， which can be suitable for a wide range of gravity density, possesses low compression strength, and elastic modulus, remains steady property in different temperatures and moistures, has no pollution on environment, is cheap in cost and is simple in manufacturing technique. Experiments verify that studying method is correct and the result is reliable.