The purpose of this research is empirically investigating organizational/managerial factors affecting BPR implementation between Korean and US companies. And we compared the critical success factors and business innovation performance of Korean companies to those of US companies based on the prior research. Seven variables that represent success of BPR implementation are identified. They are : (1) reduction of process time (2) reduction of process cost (3) upgraded skill or knowledge (4) improved quality of process output (5) improved quality of work life (6) responsiveness to customer need (7) overall perception of BPR success. The result showed that the performance of US companies is better than that of Korean companies. Especially level of overall perception of BPR success of US companies is more high than that of Korean companies. The reason is that business innovation of Korean companies is focused on functional unit and incremental improvement.