This paper investigates the role of L2 learner beliefs in study-abroad (SA) contexts. To date, the research of learner beliefs has relied mostly on survey methods, missing qualitative, critical evaluation reflecting the learners’ voice. 8y adopting multiple qualitative research methods, idiosyncratic SA experience and learners' perception of it are reported by analyzing the data of two Korean college students experiencing changes in L2 learning beliefs and L2 proficiency before and after the SA. The data were collected through language learning autobiographies, semi-structured interviews, and stimulated recall tasks by using photos uploaded to the learners' personal web blogs. The findings show that 1) changes in L2 learning beliefs are related to thedegree of legitimate peripheral participation in SA contexts and 2) L2 learners' mode of belonging to the SA community is a useful conceptual framework for explaining their L2 learning beliefs and their sense of success in SA experience. The results suggest that the crucial factor for successful SA L2 learning may not be L2-rich contexts per se but be the learners' recognition of and appreciation for L2 participation.