Progressive metal (often shortened to prog metal or prog) is a broad fusion music genre melding heavy metal and progressive rock, combining the loud "aggression" and amplified guitar-driven sound of the former with the more experimental, cerebral or quasi-classical compositions of the latter.

The music typically showcases the extreme technical proficiency of the performers and usually uses unorthodox harmonies as well as complex rhythms with frequent meter changes and intense syncopation. The rhythmic aspects are especially emphasized in the djent subgenre.

Although the genre emerged towards the late-1980s, it was not until the 1990s that progressive metal achieved widespread success. Queensrÿche, Dream Theater, Tool, Symphony X, Shadow Gallery, King's X, and Fates Warning are a few examples of progressive metal bands who achieved commercial success. Soon after the rise of the genre's popularity, other thrash and death metal bands started to incorporate elements of progressive music in their work.