With the rising importance of Mandarin Chinese since the 80s, researchers have paid more attention to the Mandarin learners of heritage backgrounds who can understand or speak Mandarin Chinese before entering Chinese as a Foreign Language (CFL) programs. However, the study of Fangyan-speaking learners of Mandarin Chinese has been long neglected and still remains scarce. This interview study was conducted with twelve Fangyan-speaking learners of Mandarin in U.S. universities with an aim of investigating the linguistic knowledge and ethno-cultural identities that Fangyan-speaking students bring to college-level CFL classrooms. Another focus of this study is to investigate the perception Fangyan-speaking students have about their linguistic abilities and what Fangyan-speaking students are perceived to be the expectations of their instructors and peers. This study was conducted in two CFL programs: a long-established dual-track program in a research university and a newly-established mixed track program in a teaching university. Both Fangyan-speaking students and their instructors were recruited for interviews and document data were collected from both students and their instructors. A modification of Krashen’s Input Hypothesis (1981) was employed in categorizing four types of Mandarin input, in which Cantonese pronunciation for reading purposes and media consumption were found to play important roles in Fangyan-speaking students’ Mandarin learning. Analysis of the data also revealed that Fangyan-speaking participants’ ethno-cultural identities may exhibit a nature of “hybridity” (Young, 1995) owing to their family immigration histories. Implications derived from the findings are offered for researchers, practitioners, and administrators of programs that serve tertiary CFL learners. / text