The present study explored when and how emotional difficulties and poor quality of life arise in the everyday lives of socially anxious individuals. 264 freshmen-year college students completed an online survey for 11 consecutive days. Comparing individuals high (HSA) and low in social anxiety, results revealed that irrespective of daily positive emotion differentiation ability, HSAs engaged daily emotion suppression strategies, pointing to inflexible emotion regulation. Furthermore, HSAs with poor daily negative emotion differentiation used the least daily cognitive reappraisal. Finally, both expressive suppression and cognitive reappraisal showed group-specific effects on daily positive affect. Daily expressive suppression was more strongly associated with diminished daily positive affect in HSAs, and HSAs benefited less in terms of daily positive affect from daily use of cognitive reappraisal. Based on these findings, emotion differentiation ability and emotion regulation appear relevant clinical targets for individuals with social anxiety disorder.