Mark Ware Isham (born September 7, 1951) is an American musician and composer. A trumpeter and keyboardist, Isham works in a variety of genres, including jazz and electronic. He is also a prolific and acclaimed composer of film scores, and has scored over 200 film and television productions since his debut in 1983.

Isham is a nine-time Grammy Award nominee, winning Best New Age Album for his 1990 self-titled album. He was nominated for an Academy Award for A River Runs Through It (1992), and a Golden Globe Award for Nell (1994). He has also been nominated for six Primetime Emmy Awards, winning Outstanding Original Main Title Theme Music for EZ Streets.