Treatise on Harmony (Traite de l'Harmonie) is a music treatise written by Jean-Philippe Rameau. The first publication of the treatise was in Paris, 1722 by Jean-Baptiste-Christophe Ballard.
The Treatise describes music and how to write it based on the modern tonal system used today in classical music. It uses the modern Major and Minor keys to teach readers what to do to achieve good sounding music based on the 12 tone music scale.
The Treatise is divided into four books.
Rameau's treatise often obtains passages written already in a very similar manner in other publications of other books by other authors.