This research investigates the impact of inventory management on company performance, specifically focusing on Return on Assets (ROA) and Return on Equity (ROE) across different life cycle stages. Utilizing panel data from 192 firms listed on the Tehran Stock Exchange over the period from 2019 to 2023, the study employs regression analysis to explore these relationships. The findings reveal significant influences of inventory management on financial performance metrics. Notably, while effective inventory management enhances ROE, its relationship with ROA is more complex, indicating potential inefficiencies in larger firms. Specifically, a one-unit increase in inventory management correlates with a decrease in ROA but positively affects ROE. The analysis further shows that during growth and maturity phases, there is a statistically significant negative relationship between inventory management and performance metrics, whereas a positive relationship is observed during the decline phase. Additionally, control variables such as financial leverage consistently demonstrate negative correlations with both ROA and ROE. This study contributes valuable insights into the intricate dynamics between inventory management and company performance across various life cycle stages.