This study explores Korean-immigrant parents' language ideologies and practices with respect to their American-born children's language development. Participants were seven ethnic Korean families composed of immigrant parents and their American-born children, aged between five and seven, in Midwestern America. Interviews in the medium of Korean with the parents, and naturally-occurring family conversations during a meal time, reading time, and play time were audio-recorded and analyzed. The findings suggest that Korean-immigrant parents have a strong desire to pass on their mother tongue to their American-born children, largely derived from their language barrier, and perception of language as an identity marker and socio-economic capital in case they return to Korea for familial obligations and economic opportunities, which represent the context-specific nature of family language policy. Language strategies, such as parental feedback and language-mixing, serve as a catalyst for the implementation of family language policy on the levels of functions, forms, and teaching of the Korean language for Korean-American children's bilingual development.