Carlos (or Carles) Baguer (March 1768 – 29 February 1808) was a Spanish classical era composer and organist. Baguer was born in Barcelona in March 1768 and received his first musical training from his uncle, Francesc Mariner, who was composer and organist in the cathedral in Barcelona. He became deputy organist to Mariner in 1786 and replaced him when his uncle died in 1789, a position he held until his own death. Although Baguer was ordained a priest, he resigned this position in 1801. He died in Barcelona in 1808, on the same day that French troops occupied Barcelona during the Peninsular War.
His students include Mateu Ferrer (who replaced Baguer as organist of the cathedral), Ramon Carnicer (between 1806 and 1808) and possibly Bernat Bertran.
He was one of the most important musical figures in Catalonia at the time and was known as a virtuosic performer and improviser on the organ.