Knowledge Management in an oranization needs a set of changes in different levels of firms; hence, Change Management has an important role for its success. This paper studies implementing knowledge management, as a new change, in the organization by emphasizing the cultural aspects in knowledge sharing. This research, first identified cultural factors in knowledge sharing, and then, used an experimental way in order to evaluate them in implementation successful knowledge management. For experimental part, a questionnaire is applied in Iranian Research Organization in Science and Technology. Five factors have been identified and studied as the cultural factors affecting knowledge sharing as, trust, commitment, job satisfaction, learning, and organizational communication. The results show that facing the resistance of people, the implementation of knowledge management will occur with a lot of resistance from the people. Therefore, the evaluation of cultural factors in this research doesn't appear in very good level. Although the organizations’s employees appreciate this change, but cultural evaluation shows that there is not adequate preparation in terms of cultural aspects in the organization.