Security is a prime concern in our modern life. Everyone wants to be as much secure as possible. We would all like to believe living in a safe and secured society. Nowadays there are various systems on the market ranging from inexpensive alarms to highly sophisticated systems requiring professional installation. The “Microcontroller Based Universal Surveillance System” a pretty essential part of any particular area. This system works as a watchdog for a particular area. It can detect any change, desirable or undesirable, at instance including motion, temperature, entrance/exit, smoke, water, battery voltage level etc. The main objective of my thesis was to design a Universal Surveillance System Using a Microcontroller which would be cost efficient and user friendly. I have programmed my code in such a way that the whole system can be customized by the user very easily. My Universal Surveillance System will not only protect our valuable but also our lives. I believe every people should equip their homes and offices with my Universal Surveillance System as it is user friendly and cost efficient.