The invention is applicable to the technical field of transformer monitoring and provides a transformer winding monitoring device, which comprises a pressure sensor, a signal conditioner, a data acquisition card and an industrial control computer, wherein the pressure sensor is connected with the signal conditioner; the signal conditioner is connected with the data acquisition card; the data acquisition card is connected with the industrial control computer; the pressure sensor is arranged on an upper clamping piece of a to-be-detected transformer for acquiring winding steady state pressure signals of the to-be-detected transformer; the signal conditioner is used for filtering the winding steady state pressure signals; the data acquisition card is used for converting the filtered winding steady state pressure signals to digital signals; and the industrial control computer is used for restoring the digital signals to pressure signals, judging whether the restored pressure signals exceeda preset signal threshold range and acquiring the monitoring result of the to-be-detected transformer according to a judgment result. After the above scheme is adopted, the transformer operation reliability is improved, the working efficiency of a worker is improved, and the power grid is ensured to operate safely and stably.