Research Findings: As the population of Hispanic children grows within U.S. preschools, it is increasingly important to understand how these classrooms facilitate school readiness, such as positive engagement with teachers, peers, and tasks, for Spanish-speaking Dual Language Learners (DLLs). A growing literature base indicates that DLL students' exposure to their native language in the classroom provides deeper access to academic content, and can foster development of essential cognitive, social-emotional, and language skills. Therefore, the current study used an observational measure to examine how teachers' Spanish language use was related to Hispanic DLLs' classroom engagement across the academic preschool year. Separate regression models were run for teacher, peer, task, and negative engagement. As expected, results indicated that teachers' Spanish use was significantly associated with children's positive engagement to peers. Teachers' Spanish use was also significantly associated with children's negative engagement, though the direction of the effect was counterintuitive, as more Spanish use was related to greater negative engagement. Teachers' Spanish use was not significantly associated with children's engagement to teachers or tasks. Practice or Policy: The findings of this study are discussed within the context of identifying a set of best practices for facilitating inclusive early learning environments for language-minority students.