Prince Sergei Petrovich Trubetskoy (Russian: Серге́й Петро́вич Трубецко́й; 29 August 1790 – 22 November 1860) was one of the organizers of the Decembrist movement.

Close to Nikita Mikhailovich Muravyov in his views, he was declared the group's leader on the eve of the December 26 uprising in 1825 but failed to appear, and instead sought refuge in the Austrian embassy.

Troubetzkoy received home education, in 1806 he started attending lectures at Moscow University.

Trubestkoy advocated Constitutional monarchy, but other Decembrists desired revolution, to execute the tsar and establish a republic (e.g. Ryleev and Pestel).

He was arrested the next day at the apartments of Count Ludwig Lebzeltern, his brother-in-law and the Austrian Empire's minister to St.