The invention discloses a high-voltage transformer health state monitoring device and a monitoring method based on acoustic characteristics. The high-voltage transformer health state monitoring device based on the acoustic characteristics comprises a non-contact acoustic wave acquirer, wherein the non-contact acoustic wave acquirer is mounted at the periphery of a transformer body; the non-contact acoustic wave acquirer is connected with a signal analysis device and an acoustic characteristic databank through an acoustic filter; the acoustic characteristic databank is further connected with a signal analysis device. By adopting the monitoring method disclosed by the invention, variation of the acoustic characteristics of the transformer is monitored, micro variation of the health state of the transformer can be reflected and tracked, the time jump point of the acoustic characteristics is particularly monitored, acoustic characteristic time slow variation points can be filtered, abnormal behaviors of the transformer can be relatively well reflected by the time jump point of the acoustic characteristics in probability, early warning signals can be transmitted at proper time, and the health indexes of the transformer can be relatively well mastered.