This research objectives to determine the good corporate governance effect toward the firm value mediated by the bank soundness ratio. This research became performed on commercial bank companies which registered on the Indonesia capital market (IDX) between 2017-2021. The sampling method using the purposive sampling. The sample used was 175 data from 35 commercial bank companies. The panel regression analysis as data analysis technique consisting of 3 variables, specifically the dependent, the independent, and the intervening variable. The outcomes of this research indicated that the good corporate governance affected significantly toward the capital adequacy, the non-performing loan, the return on asset, and the firm value. However, good corporate governance does not affect toward a loan to deposit. The capital adequacy, and the non-performingloan affect the firm value. However, the return on asset and loan to deposit does not affect toward firm value. Furthermore, only the capital adequacy which able to mediate the good corporate governance effect toward the firm value. However, the non-performing loan, the return on asset, and the loan to deposit ratio are unable to mediate the good corporate governance effect toward firm value.

Keywords : Capital Adequacy, Firm Value, Good Corporate Governance, Loan to Deposit, Non-Performing Loan, Return on Asset.