Mathematics anxiety is recognized as a significant performance impediment that affects students across multiple ethnic and economic backgrounds. However, research has yet to fully examine the possible differential effect of mathematics anxiety on underrepresented K-12 students. Specifically, given the long-standing achievement gap between African American and White students it is imperative that the possible differential effect of mathematics anxiety on African American students be addressed. The purpose of this study was to utilize the techniques of meta-analysis to summarize the effects of anxiety on mathematics achievement in K-12 African American student populations. The results suggest that anxiety has a statistically significant effect on the mathematics achievement of representative samples of African American students. Furthermore, this effect is mediated by student grade level. More representative research is needed to better ascertain the factors that promote and sustain mathematics anxiety in African American student populations. In particular, studies that disaggregate results based on student race are necessary for more robust estimates of this phenomenon.