This study empirically investigated the effects of the target costing system as well as information technology(IT) infrastructure on the knowledge management processes(i.e., socialization, externalization, combination and internalization) and the performance of a firm. This study also examined an impact of the social capital(i.e., inter-departmental communication, trust, cooperation and integration) on the adoption and development of the target costing and the IT infrastructure. The results of this study showed that inter-departmental communication, trust and integration have a significant positive impact on the adoption of the target costing. It was also found that the effects of inter-departmental communication and integration on the development of storage and transfer infrastructure are significant and positive. However, in the adoption of search infrastructure, only the impact of inter-departmental integration was significant. The results of regression analyses presented that the target costing has significant influence on the four processes of knowledge management. It was also observed that the effects of storage and transfer infrastructure on combination are significant and positive. In search infrastructure, the impact on combination and internalization was significant. According to the results of this study, it was found that when the adoption level of the target costing is high, search infrastructure mainly affects the three processes(i.e., socialization, combination and internalization). However, under a low adoption level of the target costing, the impact of storage and transfer infrastructure on the whole processes was significant and positive. Thus, it is assumed that storage and transfer infrastructure complements a low level of the target costing adoption through the active transfer and sharing of explicit and tacit knowledge.