Many peer-to-peer (P2P) networks have been widely used for file sharing. A peer acts both as a content provider and a consumer, and is granted autonomy to decide what content, with whom, and when to share. Is a p2p network an ideal vehicle for information sharing in collaborative learning? This study adopts the Theory of Planned Behavior as a basis to study the sharing behaviors on a P2P network. Due to the lack of empirical data, we built a P2P network platform to conduct an experiment in a collaborative learning setting. Through the analysis we found the intention of sharing is only positively related with subjective norm. Based on this result, we assert that subjective norm, especially the discipline from the instructor, plays a critical role in motivating students to share knowledge on a P2P network for collaborative learning. From this empirical study, a hybrid architecture combining P2P networks with servers could be more favorable for collaborative learning.