The increasing global awareness of sustainability issues regarding environmental, social, and governance (ESG) factors has become an important concern in the business world. Companies are expected to pay more attention to and integrate ESG into their business strategies to achieve sustainable growth and enhance firm value. This study aims to examine the impact of environmental, social, and governance (ESG) performance on firm value by involving capital structure as a moderating variable. The research uses a sample of 490 from 67 non-financial sector companies listed on the Indonesia Stock Exchange with an observation period from 2014 to 2023. Data analysis employs panel data regression using Eviews 12 and SPSS 16. The research findings indicate that ESG performance negatively affects firm value. Furthermore, the relationship between ESG and firm value cannot be moderated by capital structure. These findings provide new insights for managers and stakeholders regarding the importance of careful evaluation of ESG implementation in corporate strategies. This research also highlights the need for a more in-depth approach to understanding the factors that can enhance the Firm's value in the context of sustainability.