With the popularity of learner-oriented approach in language teaching, research on learners is gaining more and more importance. This paper attempts to review the empirical researches on self-efficacy in the ESL/EFL settings during the past 10 years with the purpose of depicting the extent to which the self-efficacy research in ESL/EFL has generally covered and exploring the nature, effect and implication of self-efficacy beliefs in second language learning and teaching, and hence giving a brief picture of the development of self-efficacy research in ESL/EFL. The related research on the relationship between learners' self-efficacy and learning strategy, language anxiety, attribution, gender, achievement as well as intervention research are reviewed. The paper finally concludes that self-efficacy has a significant role in second/foreign language learning. Learners' with high self-efficacy may achieve better academic results, use more learning strategies, maintain low language anxiety and keep healthy attributions. Therefore, it is important for teachers to help the students maintain properly high but accurate self-efficacy beliefs. In the end, some pedagogical suggestions are put forward.