Most existing studies have focused on the relationship between ESG ratings and financial performance or firm market value, yet few have examined how ESG ratings affect firm performance, especially Fixed Asset Ratio, leaving this issue ripe for further investigation. Our results yield three noteworthy findings regarding the relationship between ESG scores and firm performance across both local (Taiwan ESG) and international (MSCI ESG) evaluation systems. The first result indicates that higher ESG scores are associated with higher Tobin’s Q and excess returns. This suggests that firms with stronger ESG performance are more favorably valued by the market and provide better returns to shareholders. While higher Taiwan ESG scores are positively correlated with ROA, MSCI ESG scores exhibit a negative relationship. The regression also reveals a negative relationship between the ratio of fixed assets to revenue and ESG scores, consistent across both Taiwan and MSCI measures. This research seeks to help firms pursue financial returns while placing greater emphasis on environmental protection, social responsibility, and transparency—thereby guiding capital markets to value sustainable business practices and ultimately advancing the goal of sustainable development.