The invention discloses a power transformer based on nano materials, belongs to the field of power transformer manufacture, and aims at solving the problems of unstable voltage waveform of transmission voltage of power grids, redundant harmonic waves and high failure rates in the transformer devices of the prior art. The power transformer based on the nano materials comprises a shell body, a transformer body, transformer oil, the nano two-phase magnetic materials, an electric reactor and a monitoring system, wherein the interior of the shell body is hollow and of a sealed structure; the transformer body, the nano two-phase magnetic materials and the electric reactor are arranged inside the shell body; the gaps inside the shell body are filled with the transformer oil, and the monitoring system is connected with the shell body through an oil valve. The power transformer based on the nano materials is capable of achieving on-line detection in real time, low in cost and simple in process and suitable for popularization, and takes an important effect on improvement of living standards and low-carbon environmental protection.