The role of artificial intelligence (AI) has recently gained increasing attention among second language (L2) researchers. However, the emotional influences of AI-mediated instruction on English as a foreign language (EFL) students have remained an unaddressed line of research. To fill this lacuna, the present study took a qualitative approach to unveil the perceived emotions of a sample of 498 Chinese EFL learners and their corresponding emotional regulation strategies in AI-mediated L2 education. An open-ended questionnaire and a semi-structured interview were used to glean the data. The results of MAXQDA analysis evinced that Chinese EFL learners had experienced a wide spectrum of positive and negative emotions in light of AI-based L2 education. Moreover, it was found that the participants took advantage of different antecedent-focused and response-focused strategies to regulate their AI-induced emotions. The study discusses the implications of AI-based L2 education and calls for further research on the linkage of AI and L2 emotions.