Disclosed is an automobile fire extinguishing device. A foam-water spraying combined fire extinguishing system is adopted in the automobile fire extinguishing device, and the automobile fire extinguishing device is fixed in an automobile and composed of a wet type automatic-water-spraying fire extinguishing system and a pressure storage tank type foam device. When a fire occurs, the temperature is increased, a closed sprinkler head located above an engine is fractured and sprays water. Water flow passes through a pressure storage tank to spray foam to a fire area through the sprinkle head. When the fire is put out, an electromagnetic valve is closed, and foam liquid is stopped being supplied. The automobile fire extinguishing device fixed in the automobile achieves fire extinguishing and control abilities for the automobile, enhances the fire extinguishing effect on solid fire and is a novel automobile interior fire extinguishing system which is safe, reliable, economical and practical.