This study explores how corporate governance mechanisms namely board size affects the financial performance of firms, as measured by Return on Equity (ROE), in Malaysia. Based on agency theory, which emphasizes the importance of efficient governance in alleviating conflicts between shareholders and management, this study evaluates whether the element can improve firm financial performance within an emerging market framework. A dataset comprising 45 observations from nine Malaysian firms for a period of five years which are from the year 2019 to 2023 was examined using regression analysis in STATA to determine the connections between the governance factors and ROE. The findings reveal a board size showed an insignificant positive relationship with ROE, implying that merely increasing the size of the board does not necessarily lead to enhanced firm financial performance, potentially due to inefficiencies associated with larger boards. This study adds to the existing body of knowledge on corporate governance by offering insights pertinent to the Malaysian environment, with relevance for policymakers and corporate governance practices in emerging markets. Limitations such as sample size and the cross-sectional nature of the study are acknowledged, along with suggestions for future research to examine additional governance factors and longitudinal data.