Huangying-er(黃鶯兒) is regarded as one of Feng Menglong’s folk song books such as Guazhi-er(掛枝兒), Shange(山歌), and Jiazhutao(夾竹桃). Preceding researches criticized Huangying-er as ‘a fly in the ointment’, the overall study tended to be neglected. However, Huangying-er was found to have a special meaning in terms of Chinese classical literary genre. Thus, this study reviewed the significance of Huangying-er. First, this article analysis the causes of the ambiguity of the genre classification of Huangying-er. This paper consider the fact that Chaoji (嘲妓) and Xinbianbaijipingpin(新編百妓評品) influencing Huangying-er are recognized as ‘folk song’ and ‘sanqu’, the fact that the civilianization process of < Haungying-er > melody as the reason. Next, this paper analyze the features of Huangying-er as the product placed between the boundary of Sanqu(散曲) and folk song(民歌). First, many of the works of Huangying-er are mixed with the characteristics of sanqu and the folk song. In addition, Huangying-er is also distinguished from < Haungying-er > works which are included in the Fengmenglong’s Guazhi-er and Shange. Huangying-er thus reveals a boundary attribute. The signification of Huangying-er study we analyzed above, the analysis will be supplemented through research on relationship between Xinbianbaijipingpin and the culture of mockery toward female entertainers at the qinglou(靑樓). which will be presented later. This study hopes to contribute in multilateral understanding on Huangying-er of Feng Menglong.