<p>ABSTRACT In the global context, the phenomenon of urban shrinking has grown increasingly prominent in many cities. It poses challenges to urban planning and regional development, such as the occurrence of vacant houses. In the context of Japan, the demographic condition has substantially changed over the last few decades into a declining and aging population. The situation has been discussed in many articles as the main factor in the proliferation of vacant houses across the country. Regarding this issue, this study aims to examine the correlation between the age structure composition and the number of vacant houses according to the classification of vacant houses. The study employs quantitative analysis based on the official government data of vacant houses and age structure composition. The study found that there was a strong positive correlation between the age structure composition and the number of vacant houses. Furthermore, the study revealed that areas with a higher percentage of elderly residents tended to have a higher number of vacant house rates. Nevertheless, the investigation also revealed significant correlations with other age groups, indicating that vacant houses are not exclusively influenced by the elderly population but rather by a more intricate demographic landscape. Understanding the impact of age composition on vacant houses can help policymakers develop targeted strategies to address this issue. By focusing on areas with a high percentage of elderly residents, urban planners can implement initiatives to revitalize neighborhoods and reduce the number of vacant properties.</p>