Arnolt Schlick (July 18?, c. 1455–1460 – after 1521) was a German organist, lutenist and composer of the Renaissance.
He is grouped among the composers known as the Colorists. He was most probably born in Heidelberg and by 1482 established himself as court organist for the Electoral Palatinate. Highly regarded by his superiors and colleagues alike, Schlick played at important historical events, such as the election of Maximilian I as King of the Romans, and was widely sought after as organ consultant throughout his career. The last known references to him are from 1521; the circumstances of his death are unknown.
Schlick was blind for much of his life, possibly from birth. However, that did not stop him from publishing his work. He is best known for Spiegel der Orgelmacher und Organisten (1511), the first German treatise on building and playing organs. This work, highly influential during the 16th century, was republished in 1869 and is regarded today as one of the most important books of its kind. Schlick's surviving compositions include Tabulaturen etlicher lobgesang (1512), a collection of organ and lute music, and a few pieces in manuscript. The lute pieces—mostly settings of popular songs—are among the earliest published; but Schlick's organ music is even more historically important. It features sophisticated cantus firmus techniques, multiple truly independent lines (up to five—and, in one case, ten—voices), and extensive use of imitation. Thus, it predates the advances of Baroque music era by about a hundred years, making Schlick one of the most important composers in the history of keyboard music.