The purpose of this study is to determine the extent to which metacognition(MC), judgments of learning(the gap score between predicted and actual = illusion score, IS), and the degree of usage in learning strategies predict actual scores. A total of 152 middle school students were asked to predict their scores. The students were divided into quartiles based on their actual scores. The differences in MC, IS, and the use of learning strategies were analyzed for each level. In addition, to check the extent to which MC, IS, and the use of learning strategies predict actual scores, the correlation between each variable was examined, and multiple regression analyses were conducted for each of the four learning strategies. The results of the study showed that there were significant differences in MC and IS by achievement level. Among the learning strategies used, 'practice testing(PT)' and 'self-explanation (S-E)' were significantly different by achievement level. Actual scores were positively correlated with MC and negatively correlated with IS, and there was a significant negative correlation between IS and MC. The use of the four learning strategies showed a significant positive correlation with actual scores only for PT and S-E, and a significant correlation with IS only for S-E, while the correlation with MC was not significant only for 'rereading(RR)'. The use of 'highlighting/underlining' and RR did not function as predictive variables. However, PT significantly positively predicted actual scores because the degree of its use was relatively high among excellent students due to the experience of 'desirable difficulties' during learning.