民俗音乐（Folk music），又称民间音乐、民间歌谣、民间短篇诗歌等，简称民谣、民歌、民乐或民曲，于国际民间音乐协会（IFMC）之解释定义为“经过口传过程发展起来的普罗大众音乐”，也就是该音乐散布过程，纯粹是由演奏者或音乐接收者记录教习，并亲自相传所得。其范围包含歌曲、简单乐器演奏，甚至舞曲曲调与步伐。此解释与19世纪中期重新定义民间音乐、民间传说与民间舞蹈有相当重要之衍生与连带关系，一般认定，该名词与学说界定起自于1846年，英国人类学学者托马斯（W. J. Thomas）提出[来源请求]。
民间流传的歌谣。有的内容与时事政治有关。近代作曲家，有用民谣为主题来创作各种乐曲的，如德沃夏克(antonin dvorák)的《自新大陆》交响曲、柴可夫斯基(peter llyitch tchaikovsky)的《第四交响曲》；丹第(vincentd'indy)的《山歌交响曲》；哈利斯(roy harris)的《民歌交响曲》；布鲁赫(mar bruch)的《苏格兰民歌协奏曲》；威廉士沃恩(williams vaughan)的《英吉利民歌组曲》；杜宾斯基(arcadydubensky)的《史蒂芬佛斯特组曲》；以及李亚道夫(anatol constantinovitch liadov)的《八段民歌管弦乐曲》等，皆为美妙动人的音乐，受到世人普遍的欢迎。
Folk music includes both traditional music and the genre that evolved from it during the 20th century folk revival. The term originated in the 19th century but is often applied to music that is older than that. Some types of folk music are also called world music.
Traditional folk music has been defined in several ways: as music transmitted by mouth, as music of the lower classes, and as music with unknown composers. It has been contrasted with commercial and classical styles. One meaning often given is that of old songs, with no known composers; another is music that has been transmitted and evolved by a process of oral transmission or performed by custom over a long period of time.
Starting in the mid-20th century a new form of popular folk music evolved from traditional folk music. This process and period is called the (second) folk revival and reached a zenith in the 1960s. This form of music is sometimes called contemporary folk music or folk revival music to distinguish it from earlier folk forms. Smaller similar revivals have occurred elsewhere in the world at other times, but the term folk music has typically not been applied to the new music created during those revivals. This type of folk music also includes fusion genres such as folk rock, folk metal, electric folk, and others. While contemporary folk music is a genre generally distinct from traditional folk music, in English it shares the same name, and it often shares the same performers and venues as traditional folk music. Even individual songs may be a blend of the two.