The seed yield of hybrid maize varieties relies on the traits of their parental inbred lines. However, inbred lines are susceptible to environmental factors due to inbreeding challenges in field establishment, stand uniformity, and yield. To address these challenges, the laboratory experiment was conducted at Adet, and the field experiment was conducted at Bahirdar under irrigation conditions to evaluate the effects of GA concentrations and soaking durations on seed physiological quality and agronomic attributes of maize inbred line. Treatments comprised a factorial combination of four GA 3 3 concentrations (0 ppm, 75 ppm, 150 ppm, and 225 ppm) and three soaking durations (12, 18, and 24 hours). The laboratory experiment was laid out in a completely randomized design with four replications, while the field experiment was laid out in a randomized complete block design with three replications. Results indicated that the main effect of GA concentrations and soaking durations significantly influenced seed physiological quality, yield, and yield components; however, their interaction was non significant. The highest germination (95.25%, 94.31%), seedling vigor index (2842.30, 2499.63), and seed yield (4.22 t/ha, 3.44 t/ha) were achieved with 225 ppm GA₃ and 24-hour soaking, respectively, while reducing 50% maturity time (132.33, 134.83 days). The combined effect of 225 ppm GA₃ + 24 hours gave the highest emergence index (3.71) and shortest mean emergence time (6.12 days). The partial budget analysis confirmed the feasibility of treating seeds with 225 ppm GA₃, yielding a net benefit of 510,293.16 ETB/ha and a marginal rate of return of 1,420.06%. Similarly, a 24-hour soaking duration resulted in the highest net benefit (427,705.44 ETB/ha) and marginal rate of return (11,524.76%). In conclusion, 225 ppm GA 3 3 concentration and 24-hour soaking duration enhanced seed quality, field emergence, yield, and yield components. These findings recommend adopting these treatments for sustainable inbred line seed production; however, further research is needed to confirm consistency and applicability by repeating field experiments across multiple years and locations.