The invention discloses an experimental apparatus for a non-constant debris flow. The experimental apparatus comprises a water storage tank, a hopper placed with debris, a frame for installing the hopper, a tank which is obliquely arranged and has an adjustable oblique angle, and an aggregate pool for accommodating the materials from the tank, wherein the inlet of the tank is higher than the outlet of the tank, the water outlet of the water storage tank is connected with the inlet of the tank, the water in the water storage tank and the debris in the hopper converge at the inlet of the tank to form the experimental debris flow fluid; then the debris flow fluid flows into the aggregate pool along the tank; and the bottom plate of the tank is provided with a pressure sensor, and the side plates of the tank are transparent. The invention has the advantages that: the experimental apparatus is simple in operation and can be used for effectively studying the movement characteristics of the non-constant debris flow.