Previous research has demonstrated that the increasing importance of Mandarin in education and public life has led many younger Chinese-Malaysians to regard Mandarin as their mother tongue and part of their cultural identity rather than a heritage language. Fewer studies have documented the language repertoires of middle-aged and older Chinese-Malaysians. This paper presents a qualitative study of Mandarin use conducted with six Chinese-Malaysians aged 40 and older. The participants reported extensive use of Mandarin in the domains of home, work, religion, and cultural maintenance, which were served by a heritage language in the past. This indicates that the use of Mandarin by the older generation Chinese-Malaysians to engage with the contemporary linguistic world is influenced by hegemonic local and global factors. This study therefore highlights the significance of Mandarin as both an element of cultural identity and an instrument of heritage language loss.