The study examined the achievement motivation as predictor of academic achievement among Senior Secondary School II students in Edo State, Nigeria. The sample of the study consisted of 698 students who were randomly sampled from the population of 27,937 students in pubic secondary school II students in Edo Sate. The sample size was 2.5% of the entire population, which was drawn, using the multi-stage sampling technique. There are eighteen Local Government Areas in Edo State, divided into three (3) senatorial districts - Edo North (5 local Government Areas); Edo Central (6 Local Government Areas); Edo South (7 Local Government Areas). Both independent and dependent variables were measured with relevant standardized instruments. To guide the study, three (3) research questions were raised and a null hypothesis was formulated. Data collected were analyzed using Pearson r correlation coefficient and Stepwise multiple regression statistical techniques. The results showed that achievement motivation predicted students’ academic achievement in Mathematic. On the basis of the findings, it was recommended that achievement motivation should b e enhanced using appropriate psychometric strategies.