Filipino students have continued to perform significantly below international standards, as shown in assessments like PISA. Among the many factors that may contribute to this trend, teachers' assessment literacy, particularly formative assessment literacy, should not be overlooked. Existing literature on assessment literacy remains largely general in scope, predominantly focused on in-service language teachers, and rarely examines formative assessment literacy in relation to other psychological constructs such as teaching efficacy. To address these gaps, this study investigated the relationship between teaching efficacy and formative assessment literacy among BSEd Science pre-service teachers, anchored in Bandura's self-efficacy theory. Employing a descriptive correlational design, the study involved 86 respondents who had completed their teaching internship in the school year 2025-2026. Data were gathered using adapted instruments, which are self-report questionnaires, measuring teaching efficacy and formative assessment literacy. Results revealed a very high level of teaching efficacy across instruction, motivation, and classroom management. Formative assessment literacy was likewise rated very high across the conceptual, practical, and socio-emotional dimensions. Spearman's correlation further revealed that teaching efficacy for instruction had a moderately significant relationship with the conceptual and practical dimensions and a weaker relationship with the socio-emotional dimension of formative assessment literacy. Similarly, teaching efficacy for motivation showed a moderately significant relationship with the conceptual, practical, and socio-emotional dimensions. Likewise, teaching efficacy for classroom management demonstrated a moderately significant relationship across all dimensions of formative assessment literacy. These findings support strengthening teacher education programs, fostering formative assessment literacy and teaching efficacy as pre-service teachers progress toward professional practice.