The present study investigated changes in three types of anxiety by Korean heritage language learners over a year and their correlations with achievement. The study population consisted of sixteen Korean heritage students who took two semesters of a Korean class offered by a large southwestern university in the U.S. As other previous studies, Korean heritage learners showed a relatively low level of anxiety in all three different measures and had highly negative correlations with achievement, confirming that students with high anxiety had lower achievement than students with lower anxiety. Moreover, all three anxiety measures showed highly positive correlations with each other, indicating that one type of anxiety can be a predictor of other types of anxiety.