The utility model belongs to the technical field of online monitoring technology and specifically relates to a transformer winding modification on -line monitoring device, including the transformer box body, the nearly border position of transformer box body upper surface has seted up the echelonment recess, and the cover has the reinforcement casing on the recess, and four low tension terminal of fixedly connected with, the three high -voltage connection post of the transformer box body nearly terminal fixedly connected with of upper surface are nearby held to transformer box body upper surface. The utility model discloses a transformer winding modification on -line monitoring device fixed monitoring piece that is used for monitoring different positions terminal of joint respectively in through mounting groove around, it closely monitors the terminal to insert the internal portion of transformer box through the bar type vibration sensor that will monitor piece inside, promote the monitoring precision greatly, receive external disturbance's influence littleer, and the service life of the fluorescent powder is greatly prolonged, and can give remote terminal with monitor signal wireless transmission through radio signal dispensing device, makes installation more convenient, and the security promotes greatly, use more stably.