Since the 1997 foreign exchange crisis, which marked the end of the "too big to fail" convention, Korean firms have experienced considerable changes in capital investment—the driving force of corporate growth—and in corporate governance, which can be regarded as the corporate constitution linking such investment to firm value. This study analyzes how investment expenditures of domestically listed companies affect firm value through corporate governance in the post-crisis period. Under high levels of corporate governance, capital investment and R&D investment can increase firm value, whereas capital investment under low levels of corporate governance can lead to a decline in firm value. Furthermore, the analysis revealed that agency costs decrease in firms with higher levels of corporate governance. Therefore, improving corporate governance can be considered a necessary condition for investment expenditures to translate into increases in firm value.