This research studies on the efficiency of the solar drying system for agricultural products. The product is banana as 1,300 kg the cooperative group Kluay kunjanwit. By the banana peel and place it on a rack in the drying system. Save the information and weigh the mass of bananas from 8.00 am until 6.00 pm and tested until the bananas with a moisture content not exceeding 20%. From the experimental results, it was found that the maximum relative humidity is around 61.9 %, the average temperature inside greenhouse is approximate 41.7 °C, the maximum temperature is about 46.8 °C, the maximum wind speed air is around 6 m/s and the thermal efficiency of the greenhouse system is around 778.93 %. For the economic results, the payback period of greenhouse system is approximate 0.44 y.