Taiyuan is a city with more moutains, less loess resource and abundant coal gangue. This paper studied the feasibility of turning coal gangue into filling in Taiyuan region, based on successful experience home and abroad. A series of tests on physical-chemistry properties and mechanical characteristics of the coal gangue proved that coal gangue used in the experiment has good chemical properties, grain composition. The coal gangue is a kind of non-sticky coarse grained soils which can drain off water freely, and it can be used as the filling of foundation. Based on tests, this article provided a theoretical basis and a favorable reference for engineering application of coal gangue and its research and development in other areas.