Abstract. The importance of understanding the concepts in mathematics learning and the differences in the way of thinking and math skills between men and women recently, raises the question of how the understanding of male and female students on mathematical concepts. This research is a qualitative research that aims to know the understanding of junior high school students on the concept of linear equations of one variable in terms of gender differences. The research data was obtained through test-based interviews in the understanding the concept of linear equations of one variable with the subject of research of a female student and a male student in junior high school. The results showed that there was no significant difference between female subjects and male subjects; differences occurred when (1) male subjects were more complete in mentioning some of the features of Linear Equations One Variable, and (2) female subjects were better at explaining the consequences resulting from a counting operation on a linear equation of one variable with a variable or constant.