The invention discloses an automatic fire extinguishing type oil-immersed transformer. A nitrogen conveying pipe is provided with an exhaust valve. A safety chamber is arranged on the top of a transformer oil tank. A pressure releasing valve and a wiring casing pipe are arranged in the safety chamber. A nitrogen sprayer is arranged in the safety chamber and connected with the exhaust valve througha safety chamber nitrogen pipe. The automatic fire extinguishing type oil-immersed transformer is provided, contact of excess oil in the transformer oil tank and flames is effectively isolated, ignition points at the outer portion of a tank body can be effectively extinguished, the fire extinguishing quality is guaranteed, and firing losses are reduced.