This document describes a real-time transformer health monitoring system using GSM and IoT. The system monitors key indicators of distribution transformers like load currents, transformer oil temperature, winding temperature and voltage of three phases. Sensors measure these parameters and send the data via GSM to a computer server. This allows utility operators to remotely monitor transformer condition and identify issues before failures occur, improving reliability and reducing costs. The system uses an Arduino microcontroller, sensors, GSM module and ESP8266 WiFi module to measure parameters, send data via mobile networks and provide real-time transformer monitoring via IoT.