The prime minister of Tonga is the country's head of government. Tonga is a monarchy with the king, currently Tupou VI, former prime minister, as head of state. The current prime minister is Siaosi Sovaleni, who was elected on 15 December 2021 and appointed on 27 December 2021. Sovaleni was elected with 16 votes.

Tupou VI is King of Tonga. He is the younger brother and successor of the late King George Tupou V. He was officially confirmed by his brother on 27 September 2006 as the heir presumptive to the Throne of Tonga, as his brother had no legitimate children. He served as Prime Minister of Tonga from 2000 to 2006 and as Tonga's High Commissioner to Australia, and resided in Canberra from 2008, until the death of King George Tupou V on 18 March 2012, when he became King of Tonga, with the regnal name Tupou VI.