Recent evidence demonstrates that lexical-semantic connections emerge over the second year of life for monolingual children. Yet, little is known about the developing lexical-semantic organization of children acquiring two languages simultaneously. Two- to 4 year-old French-Spanish bilingual children completed a within-language auditory semantic priming task in both of their languages, while event-related potentials (ERPs) were recorded. The results revealed that bilingual children exhibited sensitivity to taxonomic relationships between words in each of their languages, but the pattern of brain activity varied across the dominant (DL) and the non-dominant (NDL) languages. While the N2 occurred for both languages, the N400 appeared for target words in the DL only and the late anterior negativity for target words in the NDL only. These findings indicate that words are organized taxonomically in the bilinguals’ lexicons. However, the patterns of brain activity suggest that common and distinct neural resources underlie lexical-semantic processing in each language.