| Country | Constitution |
| Hungary | 18 August 1949, effective 20 August 1949; revised 19 April 1972; 18 October 1989 revision ensured legal rights for individuals and constitutional checks on the authority of the prime minister and also established the principle of parliamentary oversight; 1997 amendment streamlined the judicial system |
| Iceland | 16 June 1944, effective 17 June 1944; amended many times |
| India | 26 January 1950; amended many times |
| Indian Ocean | void |
| Indonesia | August 1945; abrogated by Federal Constitution of 1949 and Provisional Constitution of 1950, restored 5 July 1959; series of amendments concluded in 2002 |
| Iran | 2-3 December 1979; revised 1989 to expand powers of the presidency and eliminate the prime ministership |
| Iraq | ratified on 15 October 2005 (subject to review by the Constitutional Review Committee and a possible public referendum ) |
| Ireland | adopted 1 July 1937 by plebiscite; effective 29 December 1937 |
| Isle of Man | unwritten; note - The Isle of Man Constitution Act of 1961 does not embody the unwritten Manx Constitution |
| Israel | no formal constitution; some of the functions of a constitution are filled by the Declaration of Establishment (1948), the Basic Laws of the parliament (Knesset), and the Israeli citizenship law; note - since May 2003 the Constitution, Law, and Justice Committee of the Knesset has been working on a draft constitution |
| Italy | passed 11 December 1947, effective 1 January 1948; amended many times |
| Jamaica | 6 August 1962 |
| Jan Mayen | void |
| Japan | 3 May 1947 |
| Jersey | unwritten; partly statutes, partly common law and practice |
| Jordan | 1 January 1952; amended many times |
| Kazakhstan | first post-independence constitution adopted 28 January 1993; new constitution adopted by national referendum 30 August 1995 |
| Kenya | 12 December 1963; amended as a republic 1964; reissued with amendments 1979, 1982, 1986, 1988, 1991, 1992, 1997, 2001; note - a new draft constitution was defeated by popular referendum in 2005 |
| Kiribati | 12 July 1979 |
| Korea, North | adopted 1948; completely revised 27 December 1972, revised again in April 1992, and September 1998 |
| Korea, South | 17 July 1948; note - amended or rewritten nine times; current constitution approved on 29 October 1987 |
| Kosovo |  ratified 9 April 2008; went into effect 15 June 2008 |
| Kuwait | approved and promulgated 11 November 1962 |
| Kyrgyzstan | adopted 5 May 1993; note - amendment proposed by President Askar AKAYEV and passed in a national referendum on 2 February 2003 significantly expanded the powers of the president at the expense of the legislature; during large-scale demonstrations in November 2006, President BAKIYEV and the opposition negotiated a new constitution granting greater powers to the parliament and the government; amendments added on 30 December 2006 redistributed some power back to the president, but both November and December 2006 versions were annulled in September 2007, and a new version was approved by referendum on 21 October 2007; the BAKIYEV-initiated referendum was criticized by Western observers for voting irregularities, particularly ballot stuffing |
| Laos | promulgated 14 August 1991 |
| Latvia | 15 February 1922; restored to force by the Constitutional Law of the Republic of Latvia adopted by the Supreme Council on 21 August 1991; multiple amendments since |
| Lebanon | 23 May 1926; amended a number of times, most recently Charter of Lebanese National Reconciliation (Ta'if Accord) of October 1989 |
| Lesotho | 2 April 1993 |
| Liberia | 6 January 1986 |
| Libya | none; note - following the September 1969 military overthrow of the Libyan government, the Revolutionary Command Council replaced the existing constitution with the Constitutional Proclamation in December 1969; in March 1977, Libya adopted the Declaration of the Establishment of the People's Authority |
| Liechtenstein | 5 October 1921 |
| Lithuania | adopted 25 October 1992 |