This study examined the relationship between conscientiousness and academic performance among Junior Secondary School students in Benue State, Nigeria. A correlational research design was adopted, and data were collected from 365 JSS III students selected through multistage sampling techniques. Conscientiousness was measured using the conscientiousness subscale of the Big Five Inventory, while academic performance was assessed using a 50-item Academic Performance Test in English Language and Mathematics. Data were analysed using Pearson Product–Moment Correlation (PPMC) at a 0.05 level of significance. The results revealed a significant positive relationship between conscientiousness and academic performance (r = .224, p = .007). The coefficient of determination indicated that conscientiousness accounted for approximately 5% of the variation in academic performance. The study concludes that conscientiousness is positively associated with academic performance among junior secondary school students. It is recommended that schools should integrate behavioural and self-regulatory skill development into counselling and classroom practices to enhance students’ academic outcomes.