This study examines the relationship of L2 learners’ motivational and attitudinal factors with the two versions (self-rated and tested) of proficiency. 79 Korean university students were assessed on measures of L2 orientations, motivation, and attitudes toward English using a questionnaire and learning autobiographies. The study also compared participants’ self-reported proficiency with their TOEIC scores. The results show that more of negative values (self-rated proficiency is lower than tested proficiency) came from students with high test scores than low-achieving students. Students defined gaining bilingual proficiency as criterion for success in L2 learning,and their expectation of such desired proficiency is significantly correlated with motivation and perceived significance of English, but not with the self-rated and tested proficiency. Multiple regression analyses suggest that students’ self-awareness of the importance of English learning significantly predicts their motivation, and linguistic L2confidence and self-assessment of target language competence are significant predictors for tested proficiency, but motivational intention is not. Potential interpretations for findings and implications for L2 pedagogy are discussed.