Prime Minister of Cambodia

Protectorate of Cambodia (1945-1949)
King Norodom Sihanouk (18 March - 13 August 1945) (1st time)
Son Ngoc Thanh (14 August - 16 October 1945) (1st time)
Prince Sisowath Monireth (17 October 1945 - 15 December 1946)
Prince Sisowath Youtevong (15 December 1946 - 15 July 1947)
Sisowath Watchayavong (25 July 1947 - 20 February 1948)
Chhean Vam (20 February - 14 August 1948)
Samdech Penn Nouth (15 August 1948 - 21 January 1949) (1st time)
Yem Sambaur (12 February - 20 September 1949 (1st time)
Ieu Koeus (20 September - 29 September 1949)
Yem Sambaur (29 September - 8 November 1949) (2nd time)

Associated state of Cambodia (1949–1953)
Yem Sambaur (8 November 1949 - 28 April 1950) (2nd time)
King Norodom Sihanouk (28 April - 30 May 1950) (2nd time)
Prince Samdech Krom Luong Sisowath Monipong (30 May 1950 - 3 March 1951)
Oum Chheang Sun (3 March - 12 October 1951) (1st time)
Huy Kanthoul (13 October 1951 - 16 June 1952)
King Norodom Sihanouk (16 June 1952 - 24 January 1953) (3rd time)
Samdech Penn Nouth (24 January - 9 November 1953) (2nd time)

Independent Kingdom of Cambodia (1953–1960)
Samdech Penn Nouth (9 November - 22 November 1953) (2nd time)
Chan Nak (23 November 1953 - 7 April 1954)
King Norodom Sihanouk (7 April - 18 April 1954) (4th time)
Samdech Penn Nouth (18 April 1954 - 26 January 1955) (3rd time)
Leng Ngeth (26 January - 3 October 1955)
Prince Norodom Sihanouk (3 October 1955 - 5 January 1956) (5th time)
Oum Chheang Sun (5 January - 29 February 1956) (2nd time)
Prince Norodom Sihanouk (1 March - 24 March 1956) (6th time)
Khim Tit (3 April - 29 July 1956)
Prince Norodom Sihanouk (15 September - 15 October 1956) (7th time)
Sam Yun (25 October 1956 - 7 April 1957)
Prince Norodom Sihanouk (9 April - 7 July 1957) (8th time)
Sim Var (26 July 1957 - 11 January 1958) (1st time)
Ek Yi Oun (11 January - 17 January 1958)
Samdech Penn Nouth (17 January - 24 April 1958) (4th time)
Sim Var (24 April - 10 July 1958) (2nd time)
Prince Norodom Sihanouk (10 July 1958 - 3 April 1960) (9th time)

Monarchy-Regency of Cambodia (1960–1970)
Prince Norodom Sihanouk (3 April - 19 April 1960) (9th time)
Pho Proeung (19 April 1960 - 28 January 1961)
Samdech Penn Nouth (28 January - 17 November 1961) (5th time)
Prince Norodom Sihanouk (17 November 1961 - 13 February 1962) (10th time)
Nhiek Tioulong (13 February - 6 August 1962) (acting)
Chau Sen Cocsal Chhum (6 August - 6 October 1962)
Prince Norodom Kantol (6 October 1962 - 25 October 1966)
General Lon Nol (25 October 1966 - 1 May 1967) (1st time)
Son Sann (1 May 1967 - 31 January 1968)
Samdech Penn Nouth (31 January 1968 - 14 August 1969) (6th time)
General Lon Nol (14 August 1969 - 9 October 1970) (2nd time)

Khmer Republic (1970-1976)
General Lon Nol (9 October 1970 - 11 March 1972) (2nd time)
Prince Sisowath Sirik Matak (11 March - 18 March 1972)
Son Ngoc Thanh (18 March - 15 October 1972) (2nd time)
Hang Thun Hak (15 October 1972 - 6 May 1973)
In Tam (6 May - 9 December 1973)
Long Boret (26 December 1973 - 17 April 1975)
Samdech Penn Nouth (17 April 1975 - 5 January 1976) (7th time)

Democratic Kampuchea (1976–1979)
Samdech Penn Nouth (5 January - 4 April 1976) (7th time)
Khieu Samphan (4 April - 13 May 1976)
Pol Pot (13 May 1976 - 7 January 1979)

People's Republic of Kampuchea (1979–1989)
Pen Sovan (27 June - 5 December 1981)
Chan Sy (5 December 1981 - 26 December 1984)
Samdech Hun Sen (14 January 1985 - 1 May 1989)

State of Cambodia (1989–1993)
Samdech Hun Sen (1 May 1989 - 2 July 1993)
Samdech Hun Sen (coequal prime minister) (2 July - 21 September 1993)
Prince Norodom Ranariddh (coequal prime minister) (2 July - 21 September 1993)
Prince Norodom Ranariddh (first prime minister) (21 September - 24 September 1993)

Kingdom of Cambodia (1993–present)
Prince Norodom Ranariddh (first prime minister) (24 September 1993 - 6 July 1997)
Ung Huot (first prime minister) (16 July 1997 - 30 November 1998)
Samdech Hun Sen (second prime minister) (21 September 1993 - 30 November 1998)
Samdech Hun Sen (sole prime minister) (30 November 1998 - Present)

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