George Thomas Armstrong (February 19, 1881[1] – September 9, 1941[2]) was a politician in Manitoba, Canada.

He served in the Legislative Assembly of Manitoba from 1915 to 1920, as a member of the Liberal Party.

The Liberals won a landslide majority in this election, and Armstrong served as a backbench supporter of Tobias Norris's government for the next five years.

He ran for re-election in the 1920 campaign[3] but finished third against Conservative John Ridley, losing by 284 votes.

In 1929, Armstrong was named county court judge for the southern judicial district of Manitoba.