© 2019 Elsevier Inc. This study investigates the impact of corporate governance on the level of information asymmetry. In addition, the study examines whether a firm's political connections have a moderating effect on this relationship. Based on a sample of leading listed local banks in the Gulf Cooperation Council (GCC) member countries, the findings indicate that proxies for corporate governance mechanisms are inversely related to proxies for information asymmetry. Specifically, greater board independence, blockholders, institutional ownership, and board size are associated with greater information asymmetry as reflected in share trading volume, market value of shares traded, and volatility of shares returns, whereas a Chief Executive Officer (CEO)’s also being on the Board of Directors is not significantly related to the level of information asymmetry. Moreover, removing insiders from the board may harm the company because outside directors lack the knowledge and experience to steer the company appropriately. Similarly, blockholders and institutional ownership both have a limited role in information dissemination in the GCC markets. Larger boards are ineffective in information dissemination because communication, coordination, and decision-making problems are greater. However, the interactions between the proxy for the firm's political connections and corporate governance mechanisms are negatively related to the level of information asymmetry. The results indicate that firms with strong corporate governance and political connections may disseminate more information than firms that are politically unconnected. The results also imply that firm-level governance mechanisms and political connections in the GCC are crucial to improve the level of a firm's transparency.