Constitutional protection of property has been considered as an essential element of liberal democratic constitution. However, since economic power is easily converted into political power, the protection of property has an aspect which contravenes democracy and political equality. Redistribution of wealth always involves a risk that governmental power would be abused. Thus, the constitutional design of property determines the success of democratization. Post-WWII economic reform in Japan is a good example to explore the constitutional design of property. After WWII, the drastic economic reform was implemented based on the idea that the concentration of wealth impedes democratization. Such economic reform was a constitutional moment just like an enactment of Constitution. This paper deals with two major questions: first, how the Japanese economic reform was justified under the post-WWII constitution; second, how the Japanese legal system could avoid the risk of abuse of redistribution.