The paper presents a design of control system for a portable refrigerator. Mechanic and software design of the system was realized for this purpose. To do this project a small metal box which has rectangular prism shape was used. Desired temperature value was provided one button. Up side of button increases temperature value, the opposite side decreases temperature values. To controlling temperature, there is a peltier which is provided cooling. Its usage is considerably easy because the temperature value is controlled by the current over the Arduino microcontroller card. It generate PWM signal to on-off control of peltier.