Research suggests that reading for understanding, especially narrative text, is difficult for children with autism spectrum disorder (ASD); yet research on how to effectively teach skills associated with reading comprehension is limited and has generally deemphasized vocabulary interventions. This single case research design study (i.e., a multiple probe across behaviors design) examined the effectiveness of teaching emotion vocabulary words to children with ASD ages 6 to 7 years. Vocabulary knowledge was taught explicitly during the repeated reading of storybooks illustrating the target emotion words. Results showed all participants increased their ability to label and define the target emotion words. Moreover, the classroom teacher indicated the intervention improved participant understanding of emotion words. Implications and future research are discussed.