The purpose of this study was to develop a measurement scale to study the impact of hotel managers' authentic leadership on employees' organizational attachment and management performance targeting five-star hotels operated in Korea. For this purpose, it was confirmed that the statistical significance of the measurement scale of the final developed subfactors of the authentic leadership variable and the influence relationship on organizational attachment and management performance, which are outcome variables. It was verified that there is a causal relationship between the hotel manager's authentic leadership and the employees' loyalty to the company and management effectiveness. The analysis results and implications are as follows: In a hotel company, the manager's sincere leadership was found to have a positive (+) effect on employees' attachment to the organization, and organizational attachment was found to have a significant positive (+) effect on management performance. First, the implications of these results are that hotel managers play a role in leading change and encourage hotel employees to understand and adapt to change, so hotel managers are essential to maintaining the competitiveness and sustainability of hotel companies. Accordingly, the more attachment to the organization increases through the hotel manager's sincere leadership, the more it can motivate hotel employees and arouse their passion and dedication to work. Thus, it appears that the more hotel managers genuinely exhibit leadership, the more employees will have a sense of responsibility and purpose for their work and be able to help provide superior service.