Purpose The purpose of this research is to investigate the effect of social capitals on organizational knowledge sharing characteristics and individual innovation activities in community of practice (CoP) of manufacturing company. Design/methodology/approach For this purpose, we divide social capitals as three dimensions, i.e. structural, relational, and cognitive dimension. Structural dimension also consists of closure and Brokerage. Relational social capital is defined as trust about colleagues, superior authorities, and organization. Then, cognitive social capital is defined as a shared understanding among individuals, such as a shared language and codes within CoP. Knowledge Sharing is defined as quantity and quality of shared knowledge. We also defines the cause and effect relationships among social capitals, organizational knowledge sharing characteristics, and individual innovation activities in CoP of manufacturing company as follows. The social capitals will have positive effects on quality of shared knowledge. Then the quality of shared knowledge will have positive effects on the individual innovation activities. This paper tested the validity of these hypothesized casual effects and the sub-hypothesized causal relationships. For the purpose, we used the Partial Least Squares (PLS) for analyzing the causal relationships. Findings Our empirical results show that social capitals of CoP mostly have effects on organizational knowledge sharing characteristics (quantity and quality of shared knowledge) and knowledge sharing activities also have effects on individual innovative activities in the workplace. In this study, these result have a significant implication that a private company will be able to gain organizational innovative performance much better by strengthening CoP supporting activities.