This study investigated the relationship between second language (L2) learners’ cultural sensitivity and their development in L2 proficiency. The learner population of interest was Uzbek students studying in Korean universities. A total of 78 Uzbek students participated in the study. In order to assess their sensitivity in cultural differences, a questionnaire scale was developed on the basis of an overview of existing models and measurement tools. The scale was composed of six constructs: interest, attentiveness, willingness to interact, empathy, open-mindedness, and behavioral adaptation. These constructs, which have been consistently identified in the literature, were assumed to represent the affective, cognitive, and behavioral aspects of individuals’ sensitivity in cross-cultural experience. Scores on the Test of Proficiency in Korean were used as a measure of proficiency in L2 Korean. The results of multiple regression analyses suggested that the students’ cultural sensitivity predicted their L2 achievement to a large extent (r = .616). Specifically, attentiveness to cultural differences, open-mindedness, and empathy were strong predictors, while interest in cultural differences, willingness to interact, and behavioral adaptation seemed to play an indirect role in their L2 ...