The invention discloses a mutifunctional plant gasification furnace. The gasification furnace comprises a shell, wherein the top of the shell is a charge port with an upper cover; the inner cavity of the shell is composed of an upper air chamber and a lower combustion chamber with fuel; the lower part of the combustion chamber is provided with a gas outlet which is connected with a stove through a pipe, a draft fan and a filter; the upper part of the air chamber is provided with an air inlet; an elastic material-pressing device is arranged between the upper cover of the charge port and the fuel in the air chamber; the upper part and lower part of the elastic material-pressing device are against the lower part of the upper cover and the upper part of the fuel respectively; and the lower part of the fuel is provided with an ignition port. The invention has the following advantages: 1) as the plant gasification furnace adopts negative-pressure combustion, flue gas can not leak and the the pollution to the environment can be avoided; 2) as the elastic material-pressing device is adopted, the fuel is always be pressed during the combustion process, the upper cover of the charge port can not be opened for pressing, the leakage of fuel gas can be avoided, the energy can be saved and the labor intensity can be reduced; and 3) the traditional ignition mode is adopted, thus the ignitionprocess is simple and convenient and is easy to control.