Conceptions of teaching and learning influence ways of teaching and learning and naturally are associated with students' motivation, self-efficacy, and achievement. Constructivist teaching and learning conceptions provide a productive learning environment to train students equipped with 21st century skills. Therefore, it is still crucial to examine preservice teachers' conceptions. This study investigates preservice teachers' conceptions of teaching and learning regarding gender and undergraduate years and reveals the relationships between preservice teachers' teaching and learning conceptions and their academic performance. Data was collected from 513 preservice teachers using the Teaching and Learning Conceptions Questionnaire. Results indicated that female preservice teachers had more constructive beliefs than males. First-year preservice teachers had the most traditional beliefs, and second and third-year preservice teachers had more constructive beliefs than seniors. Regression analysis showed that preservice teachers' constructive conceptions increased their academic performance while traditional conceptions decreased it.