To examine the specific education challenges that minority language-speaking parents encounter in teaching their children heritage language, this study conducted in-depth interviews with ten Chinese immigrant parents in Korean-Chinese multicultural families. Textual analysis of the interviews revealed that 'One Parent One Language' is a natural approach adopted by immigrant parents in their teaching practices, although it did not provide necessary or sufficient context for raising bilingual first language children. In addition, the main challenges that hinder immigrant parents' teaching practices centred on three areas: teaching methods, resource conflicts, and language environment.