The transformer is an essential part of the transmission and appropriation framework. The point of creating, transformer security structure is to oversee in such a manner, that we are utilizing microcontroller and IoT to give programmed security and continuous observing to the transformer. There are numerous flaws happening on a transformer, for example, over voltage, under voltage, extraordinary temperature, and so on. The unit is structured so that it will be good with a wide range of dispersion and force transformer of any appraising. These pack presented sensor, microcontroller, IoT module. To shield the transformer from any cataclysmic disappointment. Also, the framework shows continuous information on the PC at the working station. This framework can use for identifying issues before they happen because of this we can forestall flaws that are expensive to fix and bring about lost assistance. We give an imaginative structure to build up a framework for checking the voltage, current, temperature, and oil parameters of a transformer in a substation or in the field. The proposed structure is produced for the client to effectively perceive the transformer on the off chance that it is endured by any issues and what are the current online parameters. This framework will assist the transformers with operating easily and distinguish issues before any disastrous disappointment. P. A. Werulkar | S. S. Chopade | S. V. Pole "Smart Transformer Protection Unit" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-2 , February 2020, URL: https://www.ijtsrd.com/papers/ijtsrd29951.pdf