A fire-extinguishing device for an oil burner capable of preventing a wind blowing against the oil burner from adversely affecting combustion operation of the oil burner through the fire-extinguishing device to ensure safe combustion operation. The device includes a valve for operating an aperture through which an air chamber communicated through a wick receiving chamber to a combustion cylinder construction is communicated to an oil reservoir communicated to an ambient atmosphere. The valve is actuated to open and close the aperture when a wick is at a wick raised position and a wick lowered position, so that air may be supplied from the ambient atmosphere through the space of the oil reservoir, air chamber and wick receiving chamber to the combustion cylinder construction for combustion during combustion operation.