无调音乐，又称“无调性音乐”；是现代音乐的一种重要流派与表现形式之一，其构成方式与有调性的古典音乐具有互补意义。

该音乐形式有其构成法则，但是不同于传统音乐；

因为“无调性”，无调音乐没有调性音乐具有的调式、和声指向性，如；动，静，解决，完结等属性，也没有协和弦，不协和弦的差异，但也有观点认为；无调音乐仍有解决矢量，只是其方式不同于调式音乐。

从其构成特征来看；无调音乐是对传统音乐的一种反叛，但其构成及实践表明；无调音乐存在自然法则或自然逻辑基础，不是人为、人工规则或与自然法则无关的“创新”。

Atonality in its broadest sense is music that lacks a tonal center, or key. Atonality, in this sense, usually describes compositions written from about 1908 to the present day where a hierarchy of pitches focusing on a single, central tone is not used, and the notes of the chromatic scale function independently of one another (Kennedy 1994). More narrowly, the term atonality describes music that does not conform to the system of tonal hierarchies that characterized classical European music between the seventeenth and nineteenth centuries (Lansky, Perle, and Headlam 2001). "The repertory of atonal music is characterized by the occurrence of pitches in novel combinations, as well as by the occurrence of familiar pitch combinations in unfamiliar environments" (Forte 1977, 1).