As innovation is increasingly generated via crowdsourcing, factors that enable or impede collective innovation deserve a closer examination. This study advances the literature on crowdsourcing for innovation by examining the roles of knowledge integration and social network position in open innovation challenges. It tests the differential main effects and the interaction effect of knowledge integration and contributors’ centralized network position on collective innovation by analyzing 3,200 posts generated from 21 organization-sponsored online crowd-based open innovation challenges. Findings showed that when knowledge contributors occupy a centralized position in the networked interaction, they are less likely to generate innovative knowledge, and the benefit obtained from integrated knowledge tends to be hampered by being centralized in online interaction. This study adds a new dimension to explaining crowdsourcing for innovation by incorporating a social network perspective into crowdsourcing and open innovation research. It also sheds light on the practice of crowdsourcing by highlighting the design of platforms that can promote the integration of crowd members’ shared knowledge while encouraging diverse voices from non-centralized members of the crowd.