Research shows that experiences with nature have positive direct and indirect effects on multiple domains of child development, including language skills. However, few studies have examined the relationship between young children's language and outdoor nature settings. In this quantitative study, we compared children's language use in an indoor classroom and an outdoor nature setting. Language samples from 16 preschool children (including seven Dual Language Learners) collected in indoor and outdoor settings of a nature-based preschool were analyzed using the CLAN (Computerized Language ANalysis) program. Data analysis showed that for both the entire sample and the sample of Dual Language Learners, children's language had higher syntactic complexity measured by Mean Length of Three or Five Longest Utterances in the outdoor nature setting. The implications of the study results are discussed.