This study was designed to explore the research question: How do alliance networks of a new venture affect the venture’s speed of internationalization? To address this question, this paper builds a theoretical framework, from the network perspective, to systematically examine the effects of multiple network constructs. The constructs included in the paper represent two different approaches in the network literature, the network content approach and the network structure approach. A set of longitudinal data of new ventures in the U.S. biotechnology industry was collected and employed for data analysis. The results show that both network content (number and features of alliances and characteristics of partners) and network structure (network density) are important to new ventures’ speed of internationalization. As an important finding of this study, the moderating role of network density in new ventures’ speed of internationalization is contingent on the type of knowledge transferred in the network.