The purpose of this study is to investigate differences in knowledge management strategy are derived from empirical analysis for 79 Koream firms that implemented the knowledge management. The study examined the relationship and fitness between competitive strategy and knowledge management strategy through review of the existing theory and investigated the differences of knowledge management performance by the fitness. The empirical results showed as follow. First, the competitive strategy and knowledge management strategy showed significant association. Second, the result showed significant differences in knowledge management performance by the fitness between competitive strategy and knowledge management strategy. Specifically, the companies that take dynamic strategy in the simultaneous pursuit of differentiation and cost-leadership strategy showed high performance. And the companies that take system strategy in the cost-leadership strategy showed high performance. However, the relationship between differentiation strategy and knowledge management strategy was not statistically significant. These results imply that firms have to formulate and implement appropriate knowledge management strategy that consistent with competitive strategy.