Otto August Strandman (30 November 1875 - 5 February 1941) was an Estonian Prime Minister and a Head of State. He was born in Vanda, Undla rural municipality, Virumaa and died in Kadrina, Virumaa.

He was Estonian Prime Minister 9 May 1919 - 18 November 1919 and Elder of State 25 January 1921 - 21 November 1922.

In 1917-1918 Chairman of the Estonian Province Assembly (Eesti Maanġukogu), in 1918, Minister of Justice, 1918-1919 Minister of Agriculture of the Provisional Government. In 1918, he was arrested by the German occupation powers. In 1919, he was Prime Minister and also Minister of War, 1920-1921 Minister of Foreign Affairs, 1921 Chairman of I Riigikogu, 1924 Minister of Foreign Affairs, later Minister of Finances, 1927-1929 Estonian Ambassador to Poland, Czechoslovakia and Romania, 1933 Ambassador to France, Belgium and Vatican. 1917-1919 Member of the Estonian Province Assembly, 1919-1920 Member of the Constitutent Assembly (Asutav Kogu), 1920-1934/1937, member of the I-V Riigikogu.

Went to the Emperor Alexander State High School in Tallinn and the 5th and 7th High School in St. Petersburg, passed the final exams at the Estonian Province State High School in Tallinn. Thereafter, worked in the Tallinn Office of the Russian State Bank for three years. In 1899-1901 studied in the law department of the St. Petersburg University and in 1901-1903 in the law department of Tartu University.

1903-1905 a lawyer in Narva and in Tallinn, 1904-1905 and 1917 a member of the Tallinn City Council. Participated in the Russian revolution of 1905, after that lived in 1905-1909 in Switzerland and other European countries as an exile. 1909-1917 a barrister in Tallinn. 1917 the prosecutor of the Tallinn District Court.

Has been a member of the Council of the theatre Estonia, the Tallinn Savings and Loans Society and other non-governmental organisations.

Honoured: Cross of Freedom III/1. Honorary Doctor of Law of the Tartu University.

1941 shot himself at the time when the NKVD (People's Commissariat of Internal Affairs, here the Soviet State Secret Police) officers came to arrest him.