The aim of this thesis is to enhance the heat transfer of a solar air heater by using porous material. A comprehensive literature survey has been carried out to learn the previous researches. Depending on this literature survey, some design parameters were determined and a solar air heater was constructed to the Solar & Wind Energies Laboratory according to this parameters. In order to obtain the optimum design parameters and maximum efficiency of solar air heater, several studies have been carried out including clear and porous material assisted channels. For this purpose different configurations and designs were investigated and tested. Temperature data along the collector, average velocity of air inside the channel, pressure drop due to the porous material, power that fan and electrical heater consumes were measured and tabulated regularly. Related graphs were drawn according to the experimental results. The effect of porous material on the heat transfer and collector efficiency was discussed based on these graphs.