Abstract
The white paper indicates that existing house market in japan is small, but some may argue that existing house market share in Japan is not necessarily small. As these numerical numbers are important for housing policy, we have to understand the actual condition. In this paper, Japanese Existing house market is investigated based on multiple definitions of calculating Japanese existing house volume of transaction and existing house market share. This study suggests that there is a possibility that existing house market in japan is not small. It needs to have a clear definition of calculation to collect statistics on existing house market.