Purpose: Individuals who have higher levels of beliefs in a just world are purported to motivate themselves better than others, thereby, have higher levels of academic performance. However, previous research performed in this field conducted mainly with Western participants and secondary level school students. The present study aims to investigate the relationship between beliefs in a just world (BJW) and academic achievement. Also, this study examined gender differences in the main variables and the moderating effect of the gender on the relationship between beliefs in a just world and academic achievement with undergraduate students from Kyrgyzstan. Research Methods: A correlational research design was adopted for the current study. A convenience sample of 302 undergraduate students participated in this study. The participants completed a questionnaire, including demographics, grand point average (GPA), and measures of beliefs in a just world. Findings: Analyses revealed that personal BJW, general BJW, and a two-way interaction of gender and general BJW predicted academic achievement. Additionally, the positive relationship between general BJW and academic achievement was moderated by gender. Low levels of general BJW adversely impacted male students but did not affect female students. In this study, gender differences were also found in academic achievement, general and personal BJW. Implications for Research and Practice: Future research needs to replicate gender's moderating role on the general beliefs in a just world and academic achievement since, to our knowledge, it is a novel finding in the just world hypothesis and academic achievement research.