The invention discloses an automobile dual-fuel supply system based on a single fuel rail and a single fuel injector set, which relates to automobile fuel supply systems. The system is structurally characterized in that a gasoline fuel tank, a gasoline pump, a gasoline pressure adjustor, a gasoline one-way valve, a three-way valve, a fuel rail, a fuel injector and an engine are sequentially connected to form a gasoline fuel supply unit, a methanol fuel tank, a methanol pump, a methanol pressure adjustor, a methanol one-way valve, a three-way valve, the oil rail, the fuel injector and the engine are sequentially connected to form a methanol fuel supply unit, and an electronic control unit is respectively connected with two sensors and four executive parts to realize control and switching from the gasoline fuel supply unit to the methanol fuel supply unit. By means of the automobile dual-fuel supply system, high power performance, fuel economy, environment-friendliness in discharge and safety and reliability in control can be obtained.