Pēteris Vasks (born April 16, 1946) is a Latvian composer.

Vasks was born in Aizpute, Latvia. He trained as a double-bass player, and played in several Latvian orchestras before entering the Latvian State Conservatory to study composition. Initially, Vasks' style owed much to the aleatoric experiments of Witold Lutosławski, Krzysztof Penderecki and George Crumb. Later works included elements of Latvian folk music. Important works include Cantabile (1979) and Musica dolorosa (1984), and four string quartets, the latest of which (2003) was dedicated to the Kronos Quartet.

Vasks was the recipient of the Vienna Herder Award in 1996 and the Latvian Grand Music Award in 1997, the latter for his violin concerto "Tala Gaisma".