The purpose of this research is to create an optimal strategy to convert the Japanese medical device industry into a highly competitive power in the field by analyzing its corporate activity. In this first report, we are analyzing the market of medical products in Japan in the period from 1999 to 2003, the cause of why Japan is less than competitive in this field was studied. Multiple linear regression analysis was applied to 80% of medical devices in the domestic market. In the analysis, a dependent variable was a corporate share in the market, and explanatory variables included: a market growth rate, a global competitiveness index, a human body risk index, and quantity of products manufactured. As a result of the analysis, it was revealed that the global competitiveness and the human body risk index give respectively a positive and a negative correlation with the domestic corporate share. It is supposed that the main cause of low global competitive power in the Japanese medical device industry is that the industry tends not to develop new products due to the high risk of human life, and therefore it is difficult for the industry to develop products effectively. As a conclusion, it is necessary to research the detail activities of companies especially in this low competitive field.