Koontz is the surname of the following notable people: Charley Koontz (born 1987), American actor Dean Koontz (born 1945), American author Elizabeth Duncan Koontz (1919–1989), African-American educator Harold Koontz (1909–1984), American business consultant Joe Koontz (born 1945), American football player Lawrence L. Koontz Jr. (1940–2025), Senior Justice of the Supreme Court of Virginia Robin Koontz (born 1954), American children's book author and illustrator Roscoe L. Koontz (1922–1997), American health physicist Stephe Koontz, American politician William Henry Koontz (1830–1911), member of the U.S. House of Representatives