The Taokas people are a group of Taiwanese Plains Aborigines who are distributed along the coastal area of Miaoli County, the coastal plain of Hsinchu, and the northern Dajia area of Taichung City. The Taokas are comprised of three major groups: the Banshan group, the Houlong group, and the Hsinchu group. Currently, the Taokas Group at Houlong Township Miaoli County still use Taiwanese. The authors explore language transferral problems by the Indigenous peoples and Han people contact effects. In addition, this study focuses on fieldwork for the phonological system of this group's Taiwanese and thereby uses sociolinguistics to explores the variations and changes between different time.