The purpose of this study is to investigate whether SOX Section 404 material weaknesses manifest in real earnings management behavior. The empirical findings indicate that, compared to companies with effective internal controls, companies with existing material weaknesses in their internal controls engage in more manipulation of real activities (particularly inventory overproduction). This implies that the weak commitment by management to provide effective internal control system and high-quality financial information relates to a tendency to use real earnings management methods. Moreover, we find evidence suggesting that companies employ real earnings management (overproduction and reduction of discretionary expenses) after disclosing previous year's material weaknesses. We conjecture that the public disclosure of material weaknesses induces management to strive to mitigate the expected negative reactions of stakeholders to the disclosure by engaging in real earnings management, which is not easily detected or constrained by outsiders. Overall, this study suggests that material weaknesses in internal controls signal an environment where management is more inclined to employ real earnings management.