Abstract: Physicochemical properties and mechanical behaviors of swelling rock are tested, and the mechanical model is established. The main purpose of this investigation is to analyze and forecast the roadway mechanical behavior. Firstly, the test model of swelling rock is established, and the test is conducted. It is found the behavior of swelling rock is affected by depth, density, void ratio, water absorption ration, expansion ration, expansive force, strength and elastic modulus. Then, the mechanical model of the swelling rock is established, and the method to predict the floor heave, strain and support stress is put forward, which is verified by engineering detections and test results.