The experimental work was carried out in the summer season of 2023 at Agricultural and Bio-systems Engineering Department, Faculty of Agriculture, Damietta University, Egypt (Latitude 31°25′35″ North, Longitude 31°39′03″ East) to manufacture and develop the double ventilated solar dryer for drying chill, lemon and tomato. The manufacture dryer consists of the solar collector which attached with the drying chamber through 3 isolated pipes. All ambient and solar dryer conditions were measured using a locally calibrated solar radiation, temperature and relative humidity data loggers with thermocouples, and also a Weather Total Station. The maximum solar radiation for the dryer chamber, collector and ambient were 1000, 1000 and 1100 W/m2, respectively. The maximum temperatures for the entrance; upper, middle, lower trays; exit; and collector were 41, 64, 62.5, 61.79, 42.29, and 83.9°C, respectively. The minimum air relative humidity at entrance and exit slots were 11 and 13%, during the day hour of 2pm, while the maximum air relative humidity at entrance and exit slots were 71 and 65%, during the day hour of 9am. The decrease of moisture content ratio were decreased from 85.4, 86.6 and 88.2% fresh product to 10.46, 13.52 and 8.83% dry product in total drying time of 15, 21 and 19h for chilli, lemon and tomato, respectively in the upper tray and air suction speed of 0.6 m/s. The drying rate were decreased after the first hour of drying from 9.37, 8.46 and 8.32% to 5, 3.48 and 4.18% during total drying time of 15, 21 and 19h for chilli, lemon and tomato, respectively in the upper tray and air suction speed of 0.6 m/s. The higher values of solar collector efficiency (C) were 74.27, 75.74 and 73.09% at the day hour of (1pm) during three drying days of 29, 30 and 31/8/2023, respectively and 1.6 m/s air suction speed. The lower values of (S.R.U.E) were 46.35, 46.35 and 51.90% around the day hours between (2 and 3pm) at three drying days of 26, 27 and 28/8/2023, respectively and 0.6 m/s air suction speed. The dried amount of chilli halves, lemon slices and tomato slices for each upper tray were 32.40, 28.62 and 25.59 kg/month; 23.58, 23.58 and 20.61 kg/month and 21.33, 25.29 and 16.92 kg/month at different air suction speeds of 0.6, 1.1 and 1.6 m/s, respectively. The solar drying cost of chilli halves, lemon slices and tomato slices for each upper tray were 10.28, 11.65 and 13.03 L.E/kg.month; 14.14, 14.14 and 16.17 L.E/kg.month and 15.63, 13.18 and 19.70 L.E/kg.month at different air suction speeds of 0.6, 1.1 and 1.6 m/s, respectively. The net present worth of total cash income from drying of chilli, lemon and tomato under solar dryer was found to be 5250 L.E. The benefit cost of chilli, lemon and tomato in solar dryer was found to be 17025 L.E. So, the payback period for drying of chilli, lemon and tomato in solar dryer was found to be 98 days or (3 months and 8 days).