The aim was to determine whether there is a relationship between anxiety and mathematical performance in sixth grade primary school students, and if gender differences exist. Mathematics anxiety is a type of anxiety that affects this specific academic area or it is triggered by it. Studies have shown that students from the beginning of adolescence show mathematics anxiety and it increases as they progress through an academic environment. There is evidence to suggest that two important factors play a role in mathematics anxiety: the educational level and gender. There is consistent evidence that girls tend to be more affected by it than boys, but this has not been studied in primary school. 149 sixth grade students (mean age 140.5 months) from four schools in two Peruvian cities participated in two assessments, one that aimed to assess their level of mathematical anxiety and one that aime...