Customer misbehavior has long been considered a problem, as it is associated with human rights violations such as verbal and physical violence that care workers experience while dealing with customers. As is well known, customer misbehavior makes care workers feel disappointed in their jobs, which lowers their overall job satisfaction. Therefore, this study analyzed job satisfaction, emotional harmony, and perceived emotional worker protection measures in response to customer misbehavior among 271 care workers. First, customer misbehavior was found to have a negative relationship with job satisfaction. Care workers’ emotional dissonance was found to mediate the relationship between customer misbehavior and job satisfaction. The mediating effect can be interpreted as a negative psychological impact of customer misbehavior on care workers, which ultimately leads to a negative impact on job satisfaction. Finally, care workers’ perceived emotional labor protection policies play a moderating role in the relationship between emotional dissonance and job satisfaction, mitigating the effect of emotional distress on job satisfaction. This study contributes to the field of employment relations research by examining institutional effects such as emotional labor protection policies in situations where care work is becoming more important, such as the aging population.