The Barclays de Tolly (Russian: Баркла́й-де-То́лли) are a Baltic German noble family.

They descend from Peter Barclay, a merchant from Banff in Scotland who emigrated to Rostock in 1621.

Barclay was himself descended from the barons of Towie or Tollie in Aberdeenshire.

His son, Johann Stephan Barclay, settled in Riga and became the ancestor of the Livonian branch of the family.

He was married to Margaretha Elisabeth von Smitten (1733–1771), and they had four sons: Emil Johann, a General in the Russian service; B. Michael Bogdanovitch; C. Andrei Bogdanovitch, a Colonel; and Michael Bogdanovitch (known as Prince Michael Andreas Barclay de Tolly), a very prominent military commander who was made a count in 1813 and a prince in 1815 by Alexander I of Russia.