The invention relates to a converter transformer with a fire-fighting device, which comprises a transformer and a converter transformer sleeve, wherein the top of the transformer is welded with a first interface; the left end surface of the transformer is welded with a second interface and a third interface; the inner walls of the first interface, the second interface and the third interface are in threaded connection to the outer cylindrical surface of the converter transformer sleeve; the outer side of the cylindrical surface, close to the bottom part, of the converter transformer sleeve isprovided with a telescopic isolation tube; and the bottom of the telescopic isolation tube is provided with a socket interface. According to the converter transformer with the fire-fighting device disclosed in the invention, through starting an electric pushing rod, a sleeve rod is driven to move upwardly, the telescopic end of the telescopic isolation tube is thus driven to move upwardly, contactwith oxygen is reduced, the burning speed is reduced, a steel wire is further driven to be pulled upwardly, as a duct is stuck by the clamp, a sealing ring is further pulled out, an INERGEN gas enters the inner part of the telescopic isolation tube for extinguishing fire, the fire is automatically extinguished, manual fire extinguishing is not needed, and the converter transformer with a fire-fighting device is suitable for a converter station.