Recent evidence demonstrates that disparities by race/ethnicity and socioeconomic status in science achievement are present in the earliest grades of school. Preschool represents one potential policy solution; however, little research has explored the relationship between preschool attendance and science outcomes. This study examines whether preschool participation may improve science outcomes overall and reduce science achievement gaps by race/ethnicity, gender, and socioeconomic status. Using data from the Early Childhood Longitudinal Study of 2011, this study uses school and classroom fixed effects models with a robust set of controls to estimate the relationship between preschool attendance and early science outcomes. Results suggest that attending preschool is predictive of higher teacher-rated science ability in the fall of kindergarten but that preschool is not predictive of higher science achievement in the spring of kindergarten. The relationship is not found to consistently differ by student race, socioeconomic status, or gender, though descriptive results demonstrate that subgroups have different patterns of preschool attendance. Implications for policy and practice are discussed.