This study aims to investigate the effect of experience abroad and second language proficiency on foreign language classroom anxiety. Particularly, this study is an attempt to fill the gap in the literature about the affective outcomes after experiences abroad through the anxiety profiles of Korean learners of English as a foreign language (EFL) while taking second language (L2) proficiency into account. Of particular interest was the analysis of an emerging theme in the second language acquisition literature: tolerance of ambiguity (e.g., Dewaele & Wei, 2012). On a computerized online survey, 148 Korean EFL participants answered the Foreign Language Classroom Anxiety Scale (FLCAS; Horwitz, Horwitz, & Cope, 1986) and completed a background questionnaire to collect information regarding amount of experience abroad and English proficiency. Regression analyses show that experience abroad and L2 proficiency were jointly related to the subfactors of the anxiety scores, which had been previously calculated by a factor analysis. Additionally, the follow-up effect size analyses indicate differentiated practical significance in terms of the relationship between time spent abroad and anxiety scores. This study brings to the forefront crucial issues involving experience abroad, language learning anxiety, and English proficiency, especially with regard to the crucial concept of tolerance of ambiguity.