Abstract: State capacity is a key concept for understanding the modernization of state governance and national system with fully mobilization. State capacity as an analytical concept, however, is trapped in theoretical wilderness. Conceptual and theoretical confusion leads to many problems in empirical research. Critically building upon an extensive review of the literature on the sources and outcomes of state capacity, we reconstruct the conceptual structure of state capacity. More concretely, by fixing the defects within Michael Mann’s influential theory of state power, we define state capacity as the combination of resources and capacity, which consists of four dimensions: coercive capacity, extractive capacity, administrative capacity-I (delivering services), and administrative capacity-II (information gathering and leadership).