This study explored the relationships of self-reflection and insight with individuals' performances on various language tasks. The Self-Reflection and Insight Scale (SRIS; Grant, Franklin, & Langford, 2002) assessed individual differences in three factors: engagement in reflection, need for reflection, and insight. A high need for reflection was associated with a low vocabulary level and a small number of intrusive errors on a recognition task. A high level of insight was associated with a high accuracy rate and high response speed on a sentence-sensibility judgment task. In addition, groups who differed in need for reflection and insight did not differ on a working memory test, suggesting that need for reflection and insight account for the variation in the language tasks independent of working memory capacity. The findings suggest connections between self-reflection, insight, and proficiency in language processing. (Contains 2 tables.)