Abstract: Now a day the idea of designing the Security Based ATM banking system project is born with the observation in our real-life incidents happening around us. This GSM base project deals with avoidance of ATM theft from robbery. So, overcome the deficiency found in existing technology in our society. We are implement the new proposed system. In this system, we provide GSM based security. In case when we lost the ATM card or theft form robbery then we are essay block the transaction in proposed system. we provide double security to ATM money transaction. First, when ATM user Insert the ATM in ATM machine, he can type the password and second, then message goes through card holder via GSM then card holder can send the security code or OTP using GSM through main system and start the transaction via card holder. When we lost the ATM card then in second case card holder cannot send the security code and stop the transaction and he directly block the card using GSM system.

Keywords: GSM, AT89C51 Microcontroller, LCD, Flash magic, Keil tool.