Background: Efficiency and effectiveness in healthcare are paramount, as any deviation can result in a dire crisis, so there is a need to improve healthcare quality by implementing lean management strategies innovatively to eliminate waste, reduce costs, and resolve work issues. Aimed to: Evaluate the effect of the lean management training program on nurse managers' innovation and crisis management. Subjects and methods: Design: A quasi-experimental research design, one group (a pre-and post-intervention). Setting: the study was carried out at Belkas Central Hospital in Dakahlia Governorate. Subjects: the study sample consisted of all nurse managers working in the study setting (63). Tools: A self-administered lean management knowledge questionnaire, a lean management strategies self-reported questionnaire, an innovative work behavior scale, and a crisis management questionnaire. Results: After program implementation, nurse managers' knowledge of lean management, lean management strategies, applied lean tools, innovative work behavior, and crisis management practice improved significantly across all three program phases. In addition, the multiple comparisons reveal that every two pairs of pre- and post-, pre- and follow-up, and post- and follow-up, has a statistically significant difference in the mean score at p =.000. Conclusion: The partial (η2) values for nurse managers' lean management knowledge, lean management strategies, applied lean tools, innovative work behavior, and crisis management practice indicate that the effect size of the lean management training program for nurse managers is substantial. Recommendations: Lean management training courses should be conducted and regularly updated for all healthcare providers. More research in this area is also recommended.