This paper estimates saving rates by age group in case of Japan using National Survey of Family Income and Expenditure（NSFIE）. NSFIE is a large scale survey with sample size of about 56,400 households, though it is done once in five years. We usually have saving rates of households, but those of individual are needed to investigate the effects of the decreasing birthrate and aging population on the average saving rates of macroeconomic level. This paper uses data of number of people of younger than 18 years-old, and older than or equal to 65 years-old, then estimates the saving rates by age group in the years of 1989, 1994, 1999, 2004, 2009, and 2014. Some assumptions of transfers of income within a household are set. The results show appropriate patterns of saving rates for age group, which are consistent to the life-cycle hypothesis. These patterns are also stable through years.