The Longdu dialect is a variety of the Eastern Min branch of Chinese originating from the towns of Dachong and Shaxi in Zhongshan in the Pearl River Delta of Guangdong.

[5] According to Søren Egerod, who published an extensive study of the dialect based on fieldwork conducted in 1949, the vocabulary consists of three layers: The Longdu dialect is the mother tongue of many overseas Chinese.

"[7] This is generally ascribed to the emigration of speakers from the Longdu region to other countries, and due to the lack of inter-generational transmission.

Only Mandarin is taught to children at school, due to its status as the official national language.

In contrast, in the home, parents and grandparents teach the children only Cantonese,[8] given that the Longdu region is within Zhongshan, Guangdong, and that Cantonese is generally viewed as the lingua franca of Guangdong.