Knowledge management incorporates the systematic management of vital knowledge resources and the associated processes of creating, organizing, gathering, utilizing, diffusion and exploiting data. A key challenge emerging is learn to encourage knowledge sharing (KS) within firms because knowledge is an organization’s intellectual capital and plays an important role in gaining a competitive advantage. Isolated initiatives for promoting KS and team collaboration without taking into consideration the limitations and constraints of KS can halt any further development in the KM culture of an operation. In this paper, in addition to individual and social factors, an effect of individual perception, which is an important factor for any behavior, is studied. We first identify effective factors in KS behavior through the theory of planned behavior, six factors of trust, knowledge power, organizational motivation, organizational culture, IT and Communities of Practice (COP) as effective factors in three categories of behavioral beliefs, subjective norms and perceived behaviors are analyzed for an Iranian research center. The results of this research helps develop KS behavior and enhance performance and creativity of research in this center.