BACKGROUND: The management of fertilizers is one of the important factors that greatly affect the growth, development and yield of mung bean. OBJECTIVES: This study was conducted to investigation effect of different irrigation levels and combination humic acid and chelated Potassium on quantitative and qualitative traits of Mung bean. METHODS: This research was carried out via split plot experiment based on randomized complete blocks design (RCBD) with three replications along 2023 year. The main factor included drought stress (80 mm evaporation from class A evaporation pan or control, 120 mm evaporation from class A evaporation pan, 160 mm evaporation from class A evaporation pan) based on the daily evaporation reported from Ahvaz weather station, the closest station to the test site. Also biologic fertilizer (nonuse of biofertilizer or control, 4 L.ha-1 humic acid, 4 kg.ha-1 Chelated Potassium, Combination of 4 L.ha-1 humic acid and 4 kg.ha-1 Chelated Potassium) belonged to sub plots. RESULT: Result of analysis of variance revealed effect of drought stress and biologic fertilizer on all measured traits was significant but interaction effect of treatments (instead seed yield) was not significant. Mean comparison result of different level of drought stress indicated that maximum amount of all measured traits (instead protein content) was for 80 mm evaporation from class A evaporation pan. Also as for Duncan classification made with respect to different level of biologic fertilizer maximum and minimum amount of measured traits belonged to combination of 4 L.ha-1 humic acid and 4 kg.ha-1 Chelated Potassium and control. CONCLUSION: Therefore, in general, it can be stated that in order to achieve the maximum crop production and qualitative components, planting mung bean with 80 mm from evaporation pan with combined application of humic acid and potassium chelate fertilizer in studied areas will be recommended. پرونده مقاله