National Diet

National Diet


Coat of arms or logo
Tadamori Oshima, LDP
since April 21, 2015
Akiko Santō, LDP
since August 1, 2019
House of Councillors political groups
Government (141)

Opposition (104)

  •      CDP (32)
  •      DPFP (21)
  •      Ishin (16)
  •      JCP (13)
  •      Reiwa (2)
  •      SDP (2)
  •      N-Koku (1)
  •      Independents (17)
House of Representatives Japan Since 2017.svg
House of Representatives political groups
Government (312)

Opposition (133)

House of Councillors last election
21 July 2019 (25th)
22 October 2017 (48th)
Meeting place
Diet of Japan Kokkai 2009.jpg
National Diet Building, Nagatachō, Chiyoda-ku, Tokyo
Imperial Seal of Japan.svg
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The National Diet (国会, Kokkai)[1][2] is Japan's bicameral legislature. It is composed of a lower house called the House of Representatives, and an upper house, called the House of Councillors. Both houses of the Diet are directly elected under parallel voting systems. In addition to passing laws, the Diet is formally responsible for selecting the Prime Minister. The Diet was first convened as the Imperial Diet in 1889 as a result of adopting the Meiji Constitution. The Diet took its current form in 1947 upon the adoption of the post-war constitution, which considers it the highest organ of state power. The National Diet Building is in Nagatachō, Chiyoda, Tokyo.


The houses of the Diet are both elected under parallel voting systems. This means that the seats to be filled in any given election are divided into two groups, each elected by a different method; the main difference between the houses is in the sizes of the two groups and how they are elected. Voters are also asked to cast two votes: one for an individual candidate in a constituency, and one for a party list. Any national of Japan at least 18 years of age may vote in these elections.[3] The age of 18 replaced 20 in 2016.[4] Japan's parallel voting system is not to be confused with the Additional Member System used in many other nations. The Constitution of Japan does not specify the number of members of each house of the Diet, the voting system, or the necessary qualifications of those who may vote or be returned in parliamentary elections, thus allowing all of these things to be determined by law. However it does guarantee universal adult suffrage and a secret ballot. It also insists that the electoral law must not discriminate in terms of "race, creed, sex, social status, family origin, education, property or income".[5]

Generally, the election of Diet members is controlled by statutes passed by the Diet. This is a source of contention concerning re-apportionment of prefectures' seats in response to changes of population distribution. For example, the Liberal Democratic Party had controlled Japan for most of its post-war history, and it gained much of its support from rural areas. During the post-war era, large numbers of people were relocating to the urban centers in the seeking of wealth; though some re-apportionments have been made to the number of each prefecture's assigned seats in the Diet, rural areas generally have more representation than do urban areas.[6] The Supreme Court of Japan began exercising judicial review of apportionment laws following the Kurokawa decision of 1976, invalidating an election in which one district in Hyōgo Prefecture received five times the representation of another district in Osaka Prefecture.[7] In recent elections the malapportionment ratio amounted to 4.8 in the House of Councillors (census 2005: Ōsaka/Tottori;[8] election 2007: Kanagawa/Tottori[9]) and 2.3 in the House of Representatives (election 2009: Chiba 4/Kōchi 3).[10]

Candidates for the lower house must be 25 years old or older and 30 years or older for the upper house. All candidates must be Japanese nationals. Under Article 49 of Japan's Constitution, Diet members are paid about ¥1.3 million a month in salary. Each lawmaker is entitled to employ three secretaries with taxpayer funds, free Shinkansen tickets, and four round-trip airplane tickets a month to enable them to travel back and forth to their home districts.[11]

Other Languages
asturianu: Dieta de Xapón
azərbaycanca: Yaponiya parlamenti
беларуская: Парламент Японіі
Deutsch: Kokkai
español: Dieta de Japón
euskara: Kokkai
فارسی: دایت ملی
français: Diète du Japon
galego: Kokkai
한국어: 일본 국회
hrvatski: Kokkai
Bahasa Indonesia: Parlemen Jepang
lietuvių: Kokkai
Bahasa Melayu: Diet Jepun
Nederlands: Kokkai
日本語: 国会 (日本)
português: Dieta do Japão
română: Dieta Japoniei
Simple English: Diet of Japan
srpskohrvatski / српскохрватски: Kokkai
Türkçe: Ulusal Diet
українська: Парламент Японії