Immediate drying is the most important operation in post harvest processing for the plants which normally contain a high level of moisture and microorganisms, to avoid quality losses of these valuable, but perishable crops. The traditional practice of shade drying of cinnamon bark has negative effects on quality of the product. High ambient air temperature and relative humidity in Sri Lanka promote the insect and mould development in harvested crops. Furthermore, intensive solar radiation adversely affects to quality, causing vitamin and essential oil losses or colour changes in dried crops. This kind of problems can be overcome by adapting a hot air dryer as done for drying of many perishable products such as fruits and vegetables.