A micro-controller used to interface with natural convection setup, which fabricated to determine the natural convection heat transfer from a metal rod. In this setup,cartridge type heater fabricated using nichrome coil. LM-35 Thermocouples are connected to a heater rod which will sense the temperature and send a signal to micro-controller. A simple software developed in visual studio, which give interface the micro-controller signal to a computer then show result on screen in this software. this software perform all the calculations and graphs plotted automatically with the help of software controls, hence this will help to reduce calculation time and errors in manual calculations.