Impostor syndrome, first defined approximately 40 years ago and increasingly discussed in the organizational behavior literature, refers to a psychological phenomenon in which individuals fail to internalize objective indicators of success and positive external feedback, and instead perceive themselves as “frauds.” It emerges through the interaction of familial influences such as overly critical parenting styles and high achievement expectations in childhood, and individual characteristics including low self-esteem, perfectionism, fear of negative evaluation, and the inability to internalize success. These tendencies are further intensified within organizational contexts characterized by competitive work environments, continuous performance evaluation, high institutional expectations, and conditions that weaken employees’ sense of belonging. Impostor syndrome is not merely an individual source of distress but a significant organizational phenomenon that affects employees’ performance, productivity, psychological well-being, and organizational commitment. It reduces job satisfaction, creativity, organizational citizenship behaviors, and leadership motivation, while increasing fear of failure and turnover intentions. Individuals experiencing impostor feelings often struggle to establish strong emotional bonds with their organizations, leading to weakened affective commitment and reduced organizational identification. Nevertheless, due to the perceived high economic, social, or psychological costs of leaving, their continuance commitment may remain relatively high. Perceived workplace social support serves as an important protective factor that mitigates these negative outcomes. In conclusion, impostor syndrome prevents employees from fully realizing their potential, generating significant costs at both individual and organizational levels. Accordingly, interventions that enhance self-efficacy, development-oriented managerial practices, and organizational policies that strengthen social support are essential for reducing impostor tendencies and their adverse effects. Therefore, impostor syndrome should be regarded not only as an individual-level issue but also as a strategic organizational concern involving leadership, organizational design, and human resource management.