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Abstract The drying characteristics and quality changes of moringa and neem leaves were examined in this study in the laboratory of the department of agricultural engineering, faculty of agriculture, Cairo university and they examined by using artificial dryer, direct and indirect solar dryers. Three different drying air temperatures 40{u00B0}C, 50{u00B0}C and 60{u00B0}C and three different air velocities 0.45 m/s, 1.00 m/s and 1.50 m/s were used by artificial dryer. The initial moisture content of moringa and neem leaves were 86.7 and 84% respectively and it decreased with the increasing of drying air temperature and air velocity. The drying rate was faster at the beginning than that at the end for all treatments. By using the artificial dryer, at drying air temperature 60{u00B0}C with air velocity 1.5 m/s showed the best data, at which in dried moringa and neem leaves, the moisture content decreased to 9.35% within drying time 5.5 hours and 8.75% within drying time 10 hours respectively, the average drying rate was 14.06 and 7.525 %/h respectively, drying ratio was 4.42:1 and 4.04:1 respectively and the average evaporative rate was 28.13 gmwater/h and 15.05 gmwater/h respectively. Also, the quality tests of dried moringa leaves showed that, at air temperature 60{u00B0}C with air velocity 1.5 m/s showed the best quality in terms of higher retention of protein and potassium, while at air temperature 40{u00B0}C with air velocity 0.45 m/s showed the best quality in terms of higher retention of vitamin C and calcium. The quality tests of dried neem leaves showed that, at air temperature 50{u00B0}C with air velocity 1.5 m/s showed the best quality in terms of higher retention of flavonoids. While, at air temperature 60{u00B0}C with air velocity 1.5 m/s showed the best quality in terms of higher retention of tannins |