This Project Digital Calendar using Microcontroller is an advanced digital calendar, which displays the Date, Day, Month over the LED display. It has an 8 bit Microcontroller which runs on the Program embedded on its ROM. Separate LEDs are provided for the date, day, and month. The system has an battery backup so that it can run over all the time even during the power failure. Totally there are 31 LEDs for indicating the date and 12 LEDs for indicating the Month and 7 LEDs to indicate the day. All the above systems are controlled by the Microcontroller. In our project we are using the popular 8 bit microcontroller AT89C2051. It is a 20 pin microcontroller.