This study tested the instructional effects of emotion regulation on achievement and self-efficacy in social studies on 7th-grade middle school students(N = 117, M = 60, F = 57). Emotion regulation strategies were taught to 59 students and 58 students were in the control group. From an ANCOVA controlling for learning anxiety among the upper 25% students of pretest achievement, the experimental group differed from the control group in post-test achievement and self-efficacy among the lower 25%, the former group significantly differed from the latter. From emotion regulation × learning anxiety ANOVAs, main effects of emotion regulation and learning anxiety were significant in achievement and self-efficacy. However, there was no interaction between emotion regulation and learning anxiety.