This paper explores entrepreneurial networks in technology-based entrepreneurial teams from a social capital perspective. Through a large scale survey to all new ventures established in 65 research-based incubators in Taiwan, we have drawn 121 technology-based entrepreneurial teams from a database for this paper. Four factors were extracted from the social capital concept, including social interaction ties, partnership, mutual trust, and shared goals. Findings suggest that more innovative entrepreneurial teams perform better in social interaction ties and mutual trust than do less innovative teams. Moreover, more mutual trust within entrepreneurial teams indicates that they will have higher social interaction, partnership, and shared goals. The findings imply that building trust relationship between entrepreneurial team members is particularly important at the start-up stage.