Japan regional population decline and response

Recent demographic data indicates significant population declines in parts of Japan. Nagasaki prefecture saw a decrease of approximately 80,000 people over a five-year period, while the Mikawa region in Aichi Prefecture recorded a 2% drop in its 2025 census. In Mikawa, analysts suggest increased automation in the manufacturing sector may be contributing to a slowdown in worker inflow.

In response to these shrinking and aging demographics, academic and regional institutions are organizing symposia to discuss sustainability. Scheduled for September 2026, events hosted by Ehime University and the Science Council of Japan will focus on the future of regional cities and decentralized society models. Concurrently, Taisho University’s Institute for Regional Design will host a symposium on ‘Smart Shrinkage: Wise Town Planning’ to explore maintaining social functions and resident well-being through case studies in areas such as Kochi Prefecture, Minami-Izu Town, and Nichinan Town.

By 2025, broader urban trends emerged as Tokyo reported a 0.2% decrease due to residents moving to affordable suburbs, Osaka saw a 0.5% drop driven by high housing costs, and Fukuoka reported a 0.6% decline. Aichi Prefecture also experienced a 0.4% decline linked to industrial downsizing and automation.

To address extreme aging and labor shortages, the village of Nanmoku in Gunma Prefecture—where 65.2% of residents are aged 65 or older—has signed a sister-city agreement with Belen, Peru. Seeking to secure essential workers such as care workers and bus drivers, Mayor Saijo Hasegawa stated, “We need people from overseas if we are to survive,” as the municipality utilizes cultural exchange to prevent community collapse.