Abstract: Most of the people in residential areas face the problem of running out of water and overflow of water in water tanks due to excess supply of water. It becomes difficult for users to judge the level of water in water tanks, due to which at times of need users may run out of water. Even when the pump is turned on users will not realize when the water tank is filled which may result in overflow. Water tank monitoring system is used to sort out the issues associated with water tank. It is also possible to check the level of the water using sensor so that whenever the water goes below certain threshold limit, a notification is sent to user through the android application and user needs to turn on the pump. Also when there is overflow of water in water tank it uses sensor to detect the water level so that if the water level goes above certain limit the pump gets turned off automatically. This system prevents wastage of water.Keyword: Microcontroller, IoT, WIFI, Water Motor, LED