Aiming at the problems of low heat energy utilization rate, uneven heating of tea and low productivity, etc., in order to improve the quality and yield of tea processing, a drum-type tea hot air redryer machine was designed. The basic structure and working principle of the dryer were explained, and the key components were analyzed theoretically. The key design parameters such as the drum speed, installation angle of roller, and hot air control cabinet were determined. The CFD-DEM coupling simulation method was used to analyze the separation ratio and temperature change of tea particles in the barrel at different rotation speeds of the drum. It was found that when the rotation speed of the drum was 15r/min, the tea particles separation ratio and temperature were changed optimally, and the re-dryer effect reached the optimum. Based on the design and simulation experiments, a set of traditional tumbler tea dryers were designed to be compared with the designed re-dryer. The test results showed that when the average speed of the drum was 15r/min, the average working temperature was 130℃, when three fresh leaves were used as raw materials, the productivity, moisture content, tea break rate, power consumption rate, and effective working temperature of the re-dryer were 65kg/h, 3.5%, 0.8%, 0.6kW·h/kg and 130℃, respectively. At 130℃, the tea leaves processed by the redryer machine can reach the superstandard standards, and each index was better than that of traditional machines, which met the working requirements of the re-dryer machine.