eng Science and Education Publishing American Journal of Educational Research 2327-6150 2020-09-09 8 9 615 621 10.12691/education-8-9-2 EDUCATION2020892 article Eric Quarshie Kakraba eqkakraba@gmail.com 1 Department of Mathematics and Information & Communication Technology, Saint Francis College of Education, Hohoe, Volta Region Ghana This study investigated the effect of mastery-based learning approach on pre-service mathematics teachers¡¯ performance in geometry in Volta Region Colleges of Education, Ghana. Two research questions and two hypotheses, evaluated at the level of.05 alpha, guided the analysis. The study had adopted a quasi-experimental approach for testing. Two colleges were sampled on purpose. Participated in this study was a group of 87 first years of the four year bachelor of education pre-service mathematics teachers program. Data was collected for the research before and after the treatment using multiple choice test items. The validated instrument had a reliability of 0.80. Data analysis was carried out using descriptive statistics (mean and standard deviation) and Covariance Analysis (ANCOVA). The study found that the use of mastery-based learning approach had a positive effect on the learning achievement of pre-service teachers as compared with the traditional method of teaching geometry and there was a slightly higher mean achievement scores in favor of the male. There was a significant disparity between the mean achievement scores of students exposed to mastery-based learning approach and traditional approach of teaching elementary geometry, both pre- and post-test. Also, the achievement score of male and female pre-service teachers taught using mastery-based learning methodology was not significantly different. The study recommended among others the adoption of mastery-based learning approach in teaching geometry, since it has proven to aid improved pre-service teachers¡¯ learning achievement in geometry. http://pubs.sciepub.com/education/8/9/2/education-8-9-2.pdf mastery-based learning geometry traditional teaching approach pre-service mathematics teachers