Air energy heat pump dryer integrates two functions of hot air drying and dehumidification drying in one. It not only has the advantages of large heat of hot air drying, fast drying rate, precise control of temperature and humidity, but also has the advantages of small heat loss in the process of dehumidification drying and small lamp affected by ambient temperature. When the relative humidity of the drying medium (air) is low, the hot air drying method is adopted to rapidly improve the drying temperature and speed up the drying rate. When the relative humidity of the drying medium (air) is high, the dehumidification drying method is adopted to reduce the heat loss in the process of dehumidification.