The invention discloses an apparatus for preparing gasoline from methanol and a method of using the apparatus to prepare gasoline from methanol through a catalytic reaction. A reaction system comprises a raw material feeding terminal, a vaporizer, a heating furnace and a fixed bed reactor. The top of the fixed bed reactor is provided with a raw material input terminal, and the bottom of the fixed bed reactor is provided with a product output terminal; at least two bed layers are vertically arranged in the fixed bed reactor, and a gas distributor is arranged between the at least two layers; the raw material feeding terminal is communicated with the vaporizer and the heating furnace; the outlet of the heating furnace is communicated with the raw material input terminal of the fixed bed reactor; and the outlet of the vaporizer is communicated with the gas distributor. A system used in conventional methods for preparing gasoline from methanol has the disadvantages of high pressure, great energy consumption and long process flow. The apparatus and method provided by the invention have the advantages of simple process, short process flow, low energy consumption in operation, low investment, few by-products and capacity of allowing the content (mass percentage) of durene in gasoline to be less than 2%.