Purpose: The purpose of this study was to examine the latent dimensionality of language in dual language learners (DLLs) who spoke Spanish as their native language and were learning English as their second language. Method: Participants included 259 Spanish-English DLLs attending kindergarten. In the spring of their kindergarten year, children completed vocabulary, grammar, listening comprehension, and higher level language measures (comprehension monitoring and inferencing) in Spanish and English. Results: Two models with similar fits best describe the data. The first was a bifactor model with a single general language factor "l," plus 2 additional language factors, 1 for Spanish and 1 for English. The second model was a 4-factor model, 1 for English that included all English language measures and 3 additional factors that included Spanish vocabulary, Spanish grammar, and Spanish higher level language. Conclusions: These results indicate that a general language ability may underlie development in both Spanish and English. In contrast to a unidimensional structure found for monolingual English-speaking kindergartners, oral language appears to be multidimensional in Spanish-English DLL kindergartners, but multidimensionality is reflected in Spanish, not English. [Co-written with the Language and Reading Research Consortium (LARRC).]