Most early work on high-performance work systems (HPWS) examines only the direct relationship between a set of management practices and performance outcomes and seldom investigates the black box between them. On top of the previous individual approach, our study would take a group level approach and investigate how the HPWS may change the performance, especially the innovation performance, through changing the organization's intra-organizational social capital. Implication and contribution are discussed. Under the culture emphasizing relationships such as China, the function of this perspective should be paid more attention.