Drying, used in various sectors, is a process, which needs quite a high amount of energy. Agricultural products can deteriorate quite rapidly as their respiration continues after the harvest. A number of different methods have been used and searched to prevent the products to deteriorate and make them be used for a long time after the harvest. Drying is one of these methods. With basic meaning, drying process is removing the moisture from the agricultural products. Drying the agricultural products under the sun, a conventional drying method, has been used since ancient times. However, when this method is conducted in the open air, hygiene problems with the products emerge. Thus, it leads to serious quality loss in the products. New technologies have been searched to dry the agricultural products with the help of hot air because this method has low energy needs and long drying period. At the end of many investigations carried out, the mostly preferred properties in drying process have been revealed to be short drying period, efficient energy use, providing high quality dried products, small area needed during process; therefore, systems compatible with these properties have been designed. In this study, the drying process of 100g pineapple pieces sliced in the same sizes was performed with the help of a heater at constant temperature of 45oC and at average room temperature of 22.7oC. From the first day until the last day of experiment, measurements of pineapple slices were carried out at regular intervals; and at the end of the fifth day, it was determined that the total weight of 100g pineapple dropped to 12.35gr, which meant that the weight of the product decreased 87.65g in total. In accordance with the data obtained, the moisture rate (mr) and moisture content of the dried product were measured at every hour during drying and calculated and shown on the graphs.