There is a high demand for the diagnostic medical blood analyzer in the global medical device market. The domestic market is in infant stage, but expected to grow very fast. In this study, we attempt to provide several ways for production improvement in order to secure price competitiveness of domestic medical blood analyzer. For this purpose we identify the problems of current production process using ARENA simulation and suggest several alternatives for productivity improvement.. Five steps of TOC (Theory of Constraints) and ARENA simulation are employed to predict productivity of each alternative and to suggest further improvement.