This study systematically investigates the impact of leverage on firm value, employing an empirical approach to analyze the effects of operating leverage, financial leverage, and combined leverage on stock returns. The sample comprises non-financial firms listed on the Korean Composite Stock Price Index (KOSPI) market from 2002 to 2021. The key findings are as follows: Firstly, operating leverage, financial leverage, and combined leverage collectively demonstrate a positive influence on firm value in instances of increased sales revenue(operating income). Subsequently, the analysis delves into the nuanced dynamics of sales revenue by subdividing into increase and decrease sections. Consequently, the value relevance of the leverage effect diminishes in the context of operating leverage and combined leverage when sales revenue experiences a decrease across all sections. Additionally, financial leverage exhibits a negative impact on firm value when operating income declines by more than 10%. This study makes two notable contributions. Firstly, it assesses management risk by dissecting it into the components of operating leverage, financial leverage, and combined leverage. Secondly, it provides managerial insights by delineating a strategic direction for effectively managing management risk to maximize their firm value.