In this present work, performance study on drying mint leaves under the metrological conditions. Intensity of radiation falls on the absorber plate which transfers heat to forced air-flow inside the galvanized iron tube. Drying experiment carried out with 1 kg of mint leaves taken for drying process under the different mass-flow rate of 0.75 m/s and 1.25 m/s in serpentine flow of air. Performance of the collector and drying efficiency were 30.33% and 1.63% in first day at 0.75 m/s mass-flow rate and in the second day collector, the drying efficiency were 29.41% and 1.89% at the mass-flow rate of 1.25 m/s. The mass-flow rate of air decreased with increasing collector and drying efficiency.