Thomas Agergaard (* 23 June 1962 in Fensmark) is a Danish jazz musician (tenor saxophone, composition). Agergaard, who was introduced to jazz through his cousin's record collection, began composing as a child. He received private lessons on the saxophone, but is self-taught as a composer. He has worked with dance companies several times. In 2002 he led the supporting group, which performed at concerts in Denmark before the Jazzpar prize winner; in the following year he acted as musical director of the jazz par octet of Andrew Hill. Together with Tobias van der Pals and Morten Mogensen he also produced the first CD with works by the Danish composer Leopold van der Pals.

His list of compositions includes wind quintets, piano music and music for jazz groups and chamber orchestras, as well as multimedia installations and compositions for film. His styles range from electronics and big band music to modern classical music.

Agergaard received the DJBFA Honorary Award in 2001 and a three-year scholarship from the Danish National Art Fund in 2002.