"A field experiment was carried out during autumn season of 2019 at Field Crops Department - College of Agricultural Engineering Sciences - University of Baghdad, Iraq to study the effect of combination of mineral fertilizers, moringa leaf extract and tryptophan acid on yield and quality of three synthetic varieties of maize and the possibility of replacing part of the mineral fertilizers with these organic maters. The layout of the experiment was Randomized Complete Blocks Design in split plots arrangement with three replicates .The experiment included three synthetic varieties of maize (bohooth-5018, Baghdad-3 and Sumer) in the main plots and five fertilizer treatments(application mineral fertilizer as recommended, application 50% of mineral fertilizer + spraying moringa leaf extract at 3% , application 50% mineral fertilizer + spraying moringa leaf extract at 6% , application 50% mineral fertilizer + tryptophan acid at 50 ppm and application 50% mineral fertilizer + tryptophan acid at 100 ppm ) in the sub plots. The results showed that maize varieties had no-significant difference in all studied characters. Application 50% mineral fertilizer + spraying moringa leaf extract at 6% gave the highest grain yield (8.732 tan ha-1 )and all its components (number of ears per plant, number of rows per ear, number of grains per row) and oil percentage (10.72%).While application 50% mineral fertilizer + tryptophan acid at 100 ppm was superior in weight of 500 grains (108.89 g) and protein percentage (10.72%)."