Based on affective events theory, we used experience sampling method to explore the relationship among interpersonal justice, negative emotion, and customer orientation behavior in service encounter. Totally 200 samples are collected. Each subject recorded a total of 20 service encounters' emotional and behavioral responses within five working days. We found that every service encounter is an emotional event, and interpersonal justice felt by service providers will affect their emotions, which in turn affect their service oriented behavior. Moreover, emotional intelligence was the moderator in the relationship between event and negative emotion.