The study were conducted to investigate the influence of moringa leaf extract, humic acid, seaweed and NPK (mineral fertilizers) as foliar fertilization on the yield and storability of onion (Giza 6 cultivar) during 2019/2020 and 2020/2021 seasons. Our results indicated that, there were significant differences among the twelve fertilization treatments for yield and storability parameters in both seasons. Results revealed that, yield and its components increased by foliar application of NPK 2000 ppm+ Moringa leaf extract 5% (T9 ) treatment .The highest means of bulb fresh weight i.e. (102.87 and 99.97 g) were obtained from treatment of NPK 2000ppm+ Moringa leaf extract 5% (T9 ) ,while the lowest average bulb fresh weight (69.60 and 70.50) was recorded under control (without fertilizers) treatment, in the first and second seasons, respectively. Total yield increased by 40.66% and 47.66% in the two seasons respectively by applying NPK 2000ppm+ Moringa leaf extract 5% (T9 ) treatment as foliar application. On the other hand, Moringa leaf extract 5% (T3 ) , seaweed 3% (T5 ), and NPK 500 ppm+ Moringa leaf extract 5% (T6 ) treatments have positive effect on marketable yield percentage. Cull yields % due to foliar application with seaweed 3% (T5 ) or NPK 500 ppm+ Moringa leaf extract 5% (T6 ) treatment recorded the lowest value while, foliar application with NPK 2000 ppm (T2 ) gave the highest cull yield . Weight loss % was affected by storage period and treatments. For all treatments, the weight loss increased during .