Tuilaepa Aiono Sailele Malielegaoi, who was seated as a prime minister for 22 years holds the record for being the longest prime minister of Samoa,  while Tui Atua Tupua Tamasese Efi, who holds the office for 104 days,  holds the record for the shortest period as a prime minister.
Tuilaepa Aiono Sailele Malielegaoi
(1945) 22 years, 21 days Tui Atua Tupua Tamasese Efi
(1938) 104 days 
Tuilaepa Aiono Sailele Malielegaoi (full name, Tuilaepa Lupesoliai Neioti Aiono Sailele Malielegaoi) is a Samoan politician who has served as the Prime Minister of Samoa and Leader of the Human Rights Protection Party since 1998, and is Samoa's longest serving head of government. Tui Atua Tupua Tamasese Efi
(1938) 104 days 
