Customer mistreatment may be an unavoidable issue for the hospitality industry. Based on the Pressure–State–Response (PSR) framework, this study investigates the process of employees’ pressure, state, and responses to customer mistreatment with the moderation of mindfulness. By using structure modeling equation techniques, we find that employees with high levels of mindfulness can mitigate the impact of customer mistreatment on emotional exhaustion; however, this study unexpectedly found that mindfulness can enhance the impact of emotional exhaustion on turnover intention. This study concludes that instead of conflicting with customers, resulting in their emotional exhaustion, these employees with mindfulness may deal with customer emotions, avoiding the immediate negative impact of customer mistreatment, which is beneficial for hospitality enterprises, particularly given the present state of competition in the industry. Even so, we find that these employees with high-level mindfulness may recognize reality rather than become confused in such circumstances and may choose to leave to find a new job. As such, there is still room for future research into ways to cope with customer mistreatment without increasing the turnover intention of such employees.