The present invention discloses an automobile electrothermal burner which comprises two parts of a fuel injector and a vaporizing electric heating unit which are arranged in a same shell body. The upper half part of the shell body is provided with the fuel injector while the lower half part is provided with the vaporizing electric heating unit. A nozzle of the fuel injector passes by a center perforation of a heat insulation base of the vaporizing electric heating unit and penetrates out of the lower end face of the insulator. In the present invention, the gas injected from a spray hole is the vaporized gas of directly spontaneous combustion, thereby simplifying the structure of the fuel injector, being beneficial to simplifying the structure of a combustion chamber and being convenient for installation and maintenance, etc. The more important thing is that the automobile electrothermal burner of the present invention can ensure the burning quality and full burning, and is beneficial to saving oil and reducing the pollution caused by tail gas emission to the atmosphere. Furthermore, the problem of detonation does not occur.