This study investigated the sub-syllabic awareness of two groups of 86 Korean kindergarteners learning English as a foreign language (EFL) or English as a second language (ESL). In addition, it explored the cross-language transfer of sub-syllabic units between Korean and English by taking into account their lexical abilities with respect to the two languages. The participants were assessed in Korean and English based on their sound oddity and similarity judgments with respect to sub-syllabic units in spoken pseudo-syllables containing semivowels (e.g., /j/ and /w/) as well as on a lexical ability test. The results indicate that EFL and ESL children preferred body structure and rime structure, respectively, regardless of the language. These results provide support for the bilingual interactive activation model; that is, bilingual lexicon may be represented in language non-selective access. Further, the differences in semivowel placement between Korean and English may be a possible resource for language-specific sub-syllabic awareness.