Yiu-kio (refined songs), which refer to art songs of Beiguan music, gained its name for the delicate and exquisite singing techniques which are distinguished from melodic patterns of operas. Alternatively referred to as yiu-kio (refined songs) in writing by some scholars, refined songs involve a singer playing a clapper accompanied by a silk and bamboo ensemble while he/she is singing. Along with silk and bamboo musical instruments which are played to accompany refined songs, ti-xian and ho-xian (both are two-stringed fiddles with resonators made of coconut shells), san-xian (a three-stringed plucked-string form of music), and pin are most frequently used whereas pi-pa, yang-chin (a hammered dulcimer), and cheng (zither) are optional.

In the jargon of Beiguan, refined songs can be referred to as da-pai or xia-pei , depending on the musical form and repertoire. A xia-pei is a divertimento consisting of four or five relatively short tunes (such as The Tung-cheng Ballad, An Emerald Jade, Shu,Luo, Shuang Die Cui), whereas da-pai refers to a longer song. Some refined songs were composed to express one’s sentiments and feelings (such as Peach Blossom, and Distant Green Mountains) while most of them are accompanied by an embedded storyline (e.g.,: The Political Bride Wang Chiao- Chun, A Fortuitous Encounter, and The Case of A Black Basin). Regardless of the musical form and repertoire, all refined songs are vocal music sung in cheng-yin (classical Mandarin used in the lyrics and dialogues of Beiguan theater music and songs).

Amongst a total of approximately 70 tunes for refined songs in Beiguan music, nearly 20 tunes actually circulate among Beiguan music clubs. Famous songs include Peach Blossom, The Political Bride Wang Chiao- Chun, The Case of A Black Basin, Distant Green Mountains, the Fu-Yang Song, Drunken at the Mountain Gate, and Chase Han Shin.