In light of the expansion of globalization and the intensification of cross-cultural communication, there is an increasing necessity to learn a second language (L2). However, many L2 learners face emotional challenges throughout the learning process, which affect their learning experience and outcomes. This paper explores the emotional experiences of Chinese learners of English as a L2 and their impact on learning outcomes. Theoretical frameworks from positive psychology and educational psychology are then employed to investigate the roles of foreign language enjoyment and foreign language anxiety, as well as the moderating effects of classroom environment and social support. The results show that foreign language enjoyment has a positive effect on learning outcomes, whereas foreign language anxiety has a detrimental effect. In the case of semantic-prefix incongruence, high-level learners exhibited stronger interference effects, which indicates the complexity of affective information processing. Therefore, the paper not only deepens the comprehension of emotional factors in foreign language learning, but also provides valuable insights into foreign language teaching practices, which indicates that teachers should prioritize students affective experiences, optimize classroom environments, and offer positive social support to promote their affective engagement and learning outcomes. Future research should further explore the differences in students affective experiences in different cultural contexts to achieve more comprehensive and personalized foreign language teaching goals.