Knowledge transfer among employees is a critical enabler of organizational learning. In this article, the direct and moderating effects of the multilevel (i.e., dyadic and individual levels) antecedents of knowledge transfer are examined based on social network and knowledge management research. By analyzing the survey responses from eight R&D groups of five firms using hierarchical linear modeling, we find that structural equivalence significantly influences interpersonal knowledge transfer at the dyadic level, even when strength of ties is controlled. At the individual level, the knowledge recipient's motivational factors such as group identification and the perceived expertise of colleagues show significant effects on knowledge transfer. Finally, the effect of strength of ties at the dyadic level is more influential when the recipient's group identification is low.