This study explored elementary teachers’ mathematics teaching efficacy and epistemological beliefs. Quantitative research participants were 60 preservice elementary teachers in a Master of Education initial certification program. Three data points were used to consider the influence of a mathematics methods course and the student teaching experience. Self-report survey measures included teacher efficacy (TES), mathematics self-efficacy, a mathematics performance test, mathematics teaching efficacy (MTEBI) and mathematics epistemological beliefs (DSBQ). In a multiple regression analysis, teacher efficacy predicted mathematics teaching efficacy; mathematics self-efficacy and mathematics performance did not. Changes over time were examined through a repeated measures MANOVA. Mathematics epistemological beliefs did not change during the study. Teacher efficacy and mathematics teaching efficacy increased during the mathematics methods course. However during student teaching, mathematics teacher efficacy did not change and teacher efficacy decreased. Mathematics self-efficacy increased from the beginning to the end of the study. A repeated measures MANOVA revealed mathematics epistemological beliefs did not influence changes in mathematics self efficacy or mathematics teaching efficacy. This study qualitatively explored three novice teachers’ mathematics epistemological beliefs, analyses of the contextual and task factors impacting mathematics teaching efficacy, and epistemological beliefs’ influence on mathematics teaching efficacy. This research sought to clarify Tschannen-Moran, Woolfolk Hoy and Hoy’s (1998) integrated model of teacher efficacy. Thematic coding and analyses of interview and classroom observation data were used to create teacher profiles. Dimensions of epistemological beliefs (Schommer, SEQ, 1990) served as a framework to analyze mathematics epistemological beliefs. For analysis of the teaching context, the teachers’ school environment, student behavior and mathematics performance were observed. For analysis of the teaching task, efficacy for student engagement, classroom management, and instructional strategies were considered. Factors influencing teachers’ analyses of mathematics teaching context included availability of a mentor teacher, mandated curriculum guides, students’ backgrounds, mainstreamed special needs students, and students’ lack of number sense. Several factors not addressed by the TSES impacted analysis of the mathematics teaching task: teacher-student relationships, teachers’ mathematics content knowledge, and management of instructional time. Teachers’ epistemological beliefs influenced their definitions of the mathematics teaching task and conceptions of successful teaching, thereby impacting mathematics teaching efficacy.