Knowledge management (KM) is not simply a technological application; more importantly, it is also a social process. Human and social factors such as national culture, leadership style and organizational culture may have influence on knowledge processes in organizations. In this research, we investigated how national culture affects on leadership style, cooperation and knowledge sharing and creating culture in organizations. Constructs of national culture consist of horizontal and vertical dimensions of individualism-collectivism. Moreover, we proposed that leadership style and cooperation play roles as mediator between national culture and knowledge cultures in organization. This research was conducted in Taiwan and New Zealand. We also examined the cultural tendency of Taiwan and New Zealand and the cultural difference between these two countries. The survey result shows that Taiwan’s participants are more vertical collectivist and New Zealand’s participants are more horizontal individualistic. We also found that horizontal collectivism is positively related to transformational leadership and cooperation. Moreover, transformational leadership and cooperation are positively associated with knowledge creating culture. Based on these findings, we suggest that horizontal collectivism may be the most important cultural pattern for a knowledge-creating organization.