The purpose of this study is to investigate the moderating effects of language abilities associated with between emotionality, attention deficit hyperactivity disorder (ADHD) and peer play interactions. Two hundred fifty-two participants were 3 year olds, with 136 boys and 116 girls. They were recruited from day care centers and preschools in Gyunggi province and Incheon city. Peer play interaction was assessed by the Penn Interactive Peer Play Scale (PIPPS). Emotionality was measured by Child Behavior Questionnaire (CBQ). ADHD was assessed by teacher ratings of ADHD syndrome. Language abilities were measured by Korean Wechsler Preschool and Primary Scale of Intelligence (K-WPPSI). Teachers completed questionnaires to assess peer play interactions, emotionality, ADHD. The results revealed that language abilities moderated relationships between emotionality and play in isolation. The magnitude of associations between emotionality and play in isolation was greater for high levels of language abilities. Moreover, there were moderating effects of language abilities associated between ADHD and play disruptions. Although ADHD was significantly associated with play disruptions, the association was stronger at the higher levels than the low levels of language abilities. It can be deduced that language abilities of 3 year old children affects the protection factor between emotionality and peer play isolation; whilst, it affects the risk factor on peer play disruptions and ADHD propensity.