Inzai (印西市, Inzai-shi) is a city located in Chiba Prefecture, Japan. As of 1 November 2020, the city had an estimated population of 105,463 in 42,388 households and a population density of 850 persons per km².[1] The total area of the city is 123.80 square kilometres (47.80 sq mi).


Chiba New Town Imba Nihon-idai Station Matsumushi-dera Hokuso Hana-ga-oka Park BIGHOP Mall Inzai Inzai-Makinohara Station surroundings
Chiba New Town
Imba Nihon-idai StationMatsumushi-dera
Hokuso Hana-ga-oka ParkBIGHOP Mall Inzai
Inzai-Makinohara Station surroundings
Flag of Inzai
Official seal of Inzai
Location of Inzai in Chiba Prefecture
Location of Inzai in Chiba Prefecture
Inzai is located in Japan
Coordinates: 35°50′N 140°09′E / 35.833°N 140.150°E / 35.833; 140.150Coordinates: 35°50′N 140°09′E / 35.833°N 140.150°E / 35.833; 140.150
 • MayorMasanao Itakura (since July 2012)
 • Total123.80 km2 (47.80 sq mi)
 (November 2020)
 • Total105,463
 • Density850/km2 (2,200/sq mi)
Time zoneUTC+9 (Japan Standard Time)
-TreeJapanese Black Pine
- FlowerCosmos
Phone number0476-42-5111
Address2364 Omori, Inzai-shi, Chiba-ken 270-1396
WebsiteOfficial website
Inzai City Hall


Inzai is located in the important area of northern Chiba Prefecture connecting Tokyo and Narita. Besides Tone River that flows in the north, Lake Tega that lies in the north-west, Imba Lake that lies in the south-east of the city, the city is also surrounded by natural environment such as natural forest. the city is located approximately 20 kilometers from the prefectural capital at Chiba and within 30 to 40 kilometers from central Tokyo. It is located about 15 kilometers from Narita International Airport. The terrain is part of the Shimosa Plateau, with an elevation of 20 to 30 meters.

Surrounding MunicipalitiesEdit

Chiba Prefecture

Ibaraki Prefecture


Inzai has a Humid subtropical climate (Köppen Cfa) characterized by warm summers and cool winters with light to no snowfall. The average annual temperature in Inzai is 14.8 °C. The average annual rainfall is 1383 mm with September as the wettest month. The temperatures are highest on average in August, at around 26.3 °C, and lowest in January, at around 4.1 °C.[2]


Per Japanese census data,[3] the population of Inzai has been greatly increased since then 1980s.

Historical population
1950 31,771—    
1960 30,440−4.2%
1970 28,011−8.0%
1980 29,970+7.0%
1990 55,131+84.0%
2000 79,780+44.7%
2010 88,146+10.5%


The area of Inzai has been inhabited since the Japanese Paleolithic period, with some stone tools having been found in Kikaribyo that were used by people during that time. During the Edo period, the village of Kioroshi developed as a port at the bank of Tone River.

After the Meiji Restoration, on April 1, 1889, the town of Kioroshi, and the villages of Omori, Taisha, Funoho, Rokugo, Munakata, Hongo and Eiji were founded with the establishment of the modern municipalities system. The Meiji Era is also the golden age for steam ships in Tone River sailing from Tokyo to Chōshi. Taisha was raised to town status on March 1, 1913 and renamed Omori Town. In 1942, a pilot training center was built in Sofuke. This place was hit by Allied air raids in World War II. After the war the training center was abandoned.

On December 1, 1954, the town of Inzai was founded through the merger of the towns of Kioroshi and Taisha, and the villages of Eiji and Funaho. At the time the population was about 11,000.

The development of the Chiba New Town project and the Hokusō Line considerably boosted the development of Inzai from the mid-1980s. Inzai was elevated to city status on April 1, 1996.

On March 23, 2010, Inzai absorbed the villages of Inba and Motono (both from Inba District) to create the new and expanded city of Inzai.


Inzai has a mayor-council form of government with a directly elected mayor and a unicameral city council of 22 members. Inzai, together with the neighboring town of Sakae, contributes two members to the Chiba Prefectural Assembly. In terms of national politics, the city is part of Chiba 13th district of the lower house of the Diet of Japan.


Inzai has mixed economy dominated by large shopping centers and industrial parks. Its location and good transportation connections between Tokyo and Narita International Airport have led to numerous logistics companies establishing warehouse and distraction centers in the city. The development of Chiba New Town has also greatly increased the number of commuter residents, with over 24% of the working population traveling to Tokyo daily.



  JR EastNarita Line

  Hokusō Railway Company - Hokusō Line



Inzai has 18 public elementary schools and nine public middle schools operated by the city government, and one public high school operated by the Chiba Prefectural Board of Education. The prefecture also operates one special education school for the handicapped.


Public librariesEdit

  • Omori Library
  • Kobayashi Library
  • Sofuke Library
  • Oguradai Library

Local attractionsEdit

Notable people from InzaiEdit


  1. ^ "Inzai city official statistics" (in Japanese). Japan.
  2. ^ Inzai climate data
  3. ^ Inzai population statistics

External linksEdit