This descriptive-correlational study examined the relationship of locus of control on the academic achievement of prospective science teachers. The 40 undergraduate pre-service Teacher Education Science students with different areas of specialization participated in the study. They were asked to fill out the Locus of Control Scale developed by Gerry Yemen and James Clawson (2003). Their respective Grade Point Averages (GPA) were used to ascertain their academic performance. Pearson Product Moment Coefficient of Correlation and mean analyses were performed to analyze the data. Results of the study revealed that as an entire group and when classified according to area of specialization, the pre-service Science students have “internal” locus of control, though the Biology majors have slightly higher numerical values for “internal” locus of control in comparison to their Physics counterparts. The mean analysis showed that as an entire group, the pre-service Science students have “good” academic achievement but when classified according to area of specialization, the Biology majors have “very good” academic achievement while Physics majors have “good” academic achievement. Furthermore, results of the study revealed that there is a significant relationship between the students’ locus of control and academic achievement, which implied that students tend to have a better academic achievement if they have internal locus of control. Therefore, the current findings serve to increase our understanding of the relationship between locus of control and academic achievement.