General Thein Sein (Burmese: သိန်းစိန်) is the current prime minister of Burma (officially Myanmar). He was appointed in April 2007 by nation's ruling military junta as interim prime minister, replacing Soe Win, who was undergoing medical treatment. Thein Sein became Soe Win's permanent successor on 24 October 2007 after Soe Win's death on 12 October 2007.

Thein Sein is not a democratically elected leader. The legitimate claimant to the role of prime minister is Aung San Suu Kyi, the democratically elected leader of the National League for Democracy in Burma, who has been under house arrest since winning the election (and subsequently winning the Nobel Peace Prize) in 1990 and 1991, respectively. Though in a democratic government the position of prime minister would entail primary executive power and head-of-state status, the current Burmese dictatorship yields nearly all power to General Than Shwe, the party chairman.

Thein Sein held the position of first secretary in the ruling State Peace and Development Council junta. He is the country's fourth-highest ranking general, and also serves as the chairman of the government-sponsored National Convention Convening Commission. Thein Sein carried out high-level negotiations with Bangladesh and Cambodia.