Aim: This study aimed to determine the main factors that affect nurse practitioners' (NPs) job satisfaction, especially the relationship between organisational commitment and leadership styles in acute care practices. Background: There is little known about the influence of organisational commitment and leadership on NPs' job satisfaction within acute care hospitals. Methods: A cross-sectional design with a national online survey enrolled 1205 NPs from the Taiwan Association of Nurse Practitioners. A multiple regression model was applied to identify potential variables that associated with job satisfaction. Results: Organisational commitment (mean = 59.47), job satisfaction (mean = 173.47) and leadership style (mean ranged from 13.29 to 28) were at a moderate level. Organisational commitment, leadership style, patient load and NP advancement levels explained 63% of the variance in NPs' job satisfaction. Conclusions: Organisational commitment and leadership styles, such as idealized influence and individual consideration, are major factors that impact NPs' job satisfaction. Implications for Nursing Management: Health care organisations should develop policies targeting organisational commitment and managers' leadership styles to improve NPs' job satisfaction.