The purpose of the present study was to examine relations between children's emotional reactivity, emotion regulation and stuttering. Participants were 65 preschool children who stutter (CWS) and 56 preschool children who do not stutter (CWNS). Parents completed the Behavior Style Questionnaire (BSQ) [McDevitt S. C., & Carey, W. B. (1978). A measure of temperament in 3-7 year old children. "Journal of Child Psychology and Psychiatry and Allied Disciplines, 19," 245-253]. Three groups of BSQ items measuring emotional reactivity, emotion regulation, and attention regulation were identified by experts in children's emotions. Findings indicated that when compared to their normally fluent peers, CWS were significantly more reactive, significantly less able to regulate their emotions, and had significantly poorer attention regulation, even after controlling for gender, age, and language abilities. Findings suggest that the relatively greater emotional reactivity experienced by preschool children who stutter, together with their relative inability to flexibly control their attention and regulate the emotions they experience, may contribute to the difficulties these children have establishing reasonably fluent speech and language. Learning outcomes: The reader should be able to: (1) define emotional reactivity and emotion regulation; (2) explain how emotional reactivity and emotion regulation relate to preschool stuttering; and (3) understand recent empirical evidence linking reactivity and regulation to preschool stuttering.