A novel method to synthesize dimethyl ether (DME) is presented. When methanol is treated with aluminum metal in super it is found that critical conditions at a density of 0.39 kg/dm(3) DME is generated above 275 degreesC through a single-step procedure. The DME production increases with the temperature elevation, and it becomes the main product above 300 degreesC with by-products of hydrogen and methane. DME is considered to be produced at the formation step of methyl derivative of boehmite and/or its surface catalytic effect.