A sun tracker is a device that orients PV panel towards the sun, to maximize the energy efficiency of the system. Sun trackers are designed to enhance the power generation capacity of solar panels. In this chapter Arduino based sun tracker system is designed. Sun intensity is measured with the help of light dependent resistor (LDR), placed at PV panels. The system comprises of the Arduino board, three LDR and servo motor. Servo motor is connected to orient the PV panels in such a way that PV panel is always perpendicular to the sun rays to generate maximum energy.