An Earned Income Tax Credit (EITC) is one of the policy options for reforming income tax provisions in Japan. This study examines how tax burdens will change after introducing a US-type EITC in Japan, using the microdata from the 2007 Basic Survey of the Living Conditions of People on Health and Welfare, which was conducted by the Ministry of Health, Labour and Welfare of Japan. It shows that the US-type EITC could serve as income supplement to low-income persons.