The drying process is the most important process in the Libyan agricultural sector for agricultural products export value. Libya uses a direct drying system from solar radiation, but it provides a large energy loss and decreases the agricultural products quality. Solar air heater technology was developed to solve these problems. One indicator of the solar air heater performance is infl uenced by the solar radiation energy absorption distribution to heat the airfl ow, which can be seen from the changes in air temperature and infl uences the thermal effi ciency. The addition of fi n elements can optimize these mechanisms. This research was conducted to analyze the effect of fi n elements (geometry and fi n number) on air temperature rise through three methods i.e. measurement of air fl ow characteristics, heat transfer rate and thermal effi ciency of solar air heater. The results showed that fi n elements with a length of 1 m and a high range between 0.197 m to 0.221 m and the fi n number of 10 pieces were able to increase the air temperature from 35 0 C to 71.8 0 C so that the thermal effi ciency of solar air heater reached 51.5%. The performance of this technology can be applied to the agricultural products drying process in Libya.