Thomas Weelkes (baptised 25 October 1576 – 30 November 1623) was an English composer and organist. He became organist of Winchester College in 1598, and subsequently moved to Chichester Cathedral. His works are chiefly vocal, and include madrigals, anthems and services.

He is best known for his vocal music, especially his madrigals and church music. Weelkes wrote more Anglican services than any other major composer of the time, mostly for evensong. Many of his anthems are verse anthems, which would have suited the small forces available at Chichester Cathedral. It has been suggested that larger-scale pieces were intended for the Chapel Royal.