Tochigi栃木県
Oyama 小山市
Data last updated:
Oyama, Tochigi, Japan has a population of 165,404 (2025 national census). IPSS projections estimate 164,441 by 2030 and 150,012 by 2050 (a decrease of about 10.0% from 2020), with the share of residents aged 65+ rising from 25.3% in 2020 to 35.2%.Sources: Japan Census (Statistics Bureau), IPSS Regional Population Projections (2023)
2025Census
165,404
2030Projection
164,441
▼ -1.3%
2040Projection
158,517
▼ -4.9%
2050Projection
150,012
▼ -10.0%
Change vs. 2020 census
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Other municipalities in Tochigi (栃木県)
Data Sources
- Portal Site of Official Statistics of Japan (e-Stat)（https://www.e-stat.go.jp/）
- National Institute of Population and Social Security Research (IPSS), Regional Population Projections (2023 ed.)
* This service uses the e-Stat API but its content is not guaranteed by the Japanese government.
Oyama Population Table (1980–2050)
Population by year: national census results (restated to current municipal boundaries) and IPSS (2023) projections based on the 2020 census.
| Year | Population | vs 2020 | Type |
|---|---|---|---|
| 1980 | 127,226 | ▼ -23.7% | Census |
| 1985 | 134,242 | ▼ -19.5% | Census |
| 1990 | 142,262 | ▼ -14.6% | Census |
| 1995 | 150,115 | ▼ -9.9% | Census |
| 2000 | 155,198 | ▼ -6.9% | Census |
| 2005 | 160,150 | ▼ -3.9% | Census |
| 2010 | 164,454 | ▼ -1.3% | Census |
| 2015 | 166,760 | ▲ +0.1% | Census |
| 2020 | 166,666 | — | Census |
| 2025 | 165,404 | ▼ -0.8% | Census |
| 2030 | 164,441 | ▼ -1.3% | Projection |
| 2035 | 161,918 | ▼ -2.8% | Projection |
| 2040 | 158,517 | ▼ -4.9% | Projection |
| 2045 | 154,463 | ▼ -7.3% | Projection |
| 2050 | 150,012 | ▼ -10.0% | Projection |
About Oyama
Overview
Oyama (小山市) is a municipality in Tochigi, Japan, with a population of 165,404 as of 2025.
Population Projection of Oyama
According to projections by Japan's National Institute of Population and Social Security Research (IPSS), Oyama's population is expected to reach 164,441 by 2030 (-1.3%), 158,517 by 2040 (-4.9%), and 150,012 by 2050 (-10.0%). A modest population change is expected.
Aging Rate of Oyama
The aging rate (percentage of residents aged 65 and over) is 25.3% as of 2020 and is projected to rise to 35.2% by 2050. The aging rate will remain below the most severe Japanese averages.
National Comparison
Oyama's demographic trajectory is similar to the national average.
National and Prefectural Rank
- Population decline rate: Ranked #1616 out of 1903 municipalities nationwide.
- Aging rate in 2050: Ranked #1601 out of 1903 nationwide.
- Population size: Ranked #229 out of 1917 nationwide.
- Related: National rankings / All municipalities in Tochigi
Earnings in Tochigi (栃木県): Average salary in Tochigi (栃木県) by age, gender and company sizejpsalary / MHLW Basic Survey on Wage Structure