Abstract: As an important part of the power system, the transformer is very important for the safe and stable operation of the power grid. During the operation of the transformer, the internal insulating oil will produce a large amount of gas. By collecting various gas data generated in the transformer oil, analyzing the gas data, and using the moving average method to obtain the predicted value of the internal gas data, the early warning of the transformer can be realized, It is convenient for operation and maintenance personnel to find transformer defects in advance, reduce the probability of failure, and ensure the safe and stable operation of equipment and reliable power supply service.