Background: Lean management practice becomes a critical role for organizational success and healthcare sectors are applying the lean practice to promote healthcare quality and patient satisfaction by improving organizational performance. The rate of organizational performance is also depending on the firm culture that means how stakeholders accept and think about the organization. Nearly every healthcare sectors in other countries apply the lean practice to improve healthcare process, however, there is a little evidence that shows how lean implementation improve performance and how the organizational culture impact on lean practice to increase organizational performance. This study analyzes the impact of organizational culture on lean implementation practice for improving organizational performance in Private hospitals, in Myanmar. Purpose: To examine the impact of organizational culture on lean implementation practice in private hospitals to increase organizational performance. Method: Quantitative study was carried out to investigate how the organizational cultureimpact on the lean practice for improving organizational performance. A self-administered questionnaire was used to collect primary data. Participants are all employees (doctors, nurse, supervisors, managing directors, and clinical staffs) in 15 targeted private hospitals and who have at least a bachelor level of education and aged not less than 18 years and not more than 60 years at the time of research. Results: A total of 333 participants completed the questionnaire. In this study, according to multiple linear regression analysis, there was a positive impact of lean implementation practice on organizational performance, r = 0.785, n = 333, p < 0.05. The result also showed that positive effect of organizational culture on organizational performance, r = 0.797, n =333, p < 0.05. Organizational culture of the hospital also had positive impact on the lean practice implementation were positively correlated, r = 0.656, n = 333, p < 0.05. Pearson correlation also approved that there were positive significant associations between lean practice implementation, organizational culture and organizational performance (r = 0.625, 0.704, and 0.681) respectively at p-value < 0.05.