Self-efficacy reflects the extent to which students believe that they can successfully perform in school. It usually positively correlated with outcome expectations but it is possible that a student's has high self-efficacy does not transform into a high academic achievement. This study sought to find out the relationship between chemistry students' self-efficacy and their academic achievement in senior secondary schools in North-central, Nigeria. The study is an ex-post facto research and is a descriptive survey. The subjects of the study were one thousand one hundred and fifty (1150) senior secondary school III chemistry students selected from Kogi, Kwara and Niger States of Nigeria. The data collected were analyzed using descriptive and inferential statistics of mean, percentage and Pearson Product Moment Correlation. The findings revealed that no significant relationship existed between self-efficacy and the academic achievement of the chemistry students. The study concludes that students' self-efficacy needs to be complemented with a host of other factors to achieve high academic achievement in Chemistry. It is therefore recommended that attention be paid to other factors necessary for better students' achievement in chemistry to complement students' high self-efficacy, so that a combination of these factors could result in high academic achievement in Chemistry.