External management consultants have been increasingly employed by owners of complex construction projects (CCPs) to foster management innovation and improve their organizational capability. However, the dynamics of the owner-consultant collaboration process in such projects are still unknown. To bridge this gap, this paper explores the roles of external consultant involvement in fostering management innovation and developing an organizational capability in CCPs. Based on survey data collected from 102 such projects across different types in China, the partial least square-structural equation modeling analysis results uncover the positive effect of external consultant involvement in creating management innovation and building organizational capability. In particular, the mediating role of management innovation is identified in the exploration and transformation learning processes with external consultants involved. The findings of this study provide a novel explanation for the creation of management innovation in CCPs through external consultant involvement and useful guidance to project owners to better identify and utilize external consultants in the future.