Social performance is associated with producing good relationships in social communication. In recent years, there has been a growing emphasis on the importance of collaborative problem- solving in social communication. Aiming to enhance collaborative problem-solving, we investigated the characteristics of behavioral signals that impact social performance. In this paper, we analyzed the eye movements and facial expressions of pairs of participants working on a collaborative problem-solving task online. Our eye movement analysis showed that the lower the percentage of looking at the conversation partner is and the higher the percentage of looking outside is, the lower is the social performance. Our facial expression analysis showed that the lower the intensity of expression is in inner brow raiser, the cheek raiser, and the lip corner puller, the lower is the social performance.