The purpose of this study is to examine the factors influencing knowledge sharing. Sample population for the study composed of all 23 academic staff of the Faculty of Education at Ferdowsi University. Based on the literature, thirteen factors were recognized as the most important factors influencing knowledge sharing. However, based on the matrix factor, nine factors (communication, perceived IT, perceived usefulness of IT, Teamwork, Strategy, Trust, Self efficiency, Sentimental commitment, and knowledge nature) were inferred.According to the results of multiple regression test, factors such as strategy, trust, and self efficiency were the three essential factors that impacted greatly on explanation of knowledge sharing behavior.