This study aims to understand teacher emotions through interviewing 53 primary teachers in Hong Kong and Mainland China. Content analysis was employed to analyze the data. Teachers reported 68 different types of emotions which decreases as distance from the teachers increases at the five nested ecological system--microsystem, mesosystem, exosystem, macro-system, and chronosystem. Teachers mentioned the most emotions at the microsystem level (50 emotions), followed by the "exosystem" (36), the mesosystem (30), the "macrosystem" (10), and the chronosystem (seven) levels. These emotions comprised 34 positive emotions (e.g., happiness, caring, pride) and 34 negative emotions (e.g., pressure, sadness, worry). Attention should be paid to the high proportion (50%) of negative emotions described by Hong Kong and Mainland China teachers. Findings may help teachers to understand how to regulate their emotions but also provide strong references for teacher education, teaching, and teacher lives.