The study's main objective was to determine the best-fit model for science curriculum implementation of public secondary science teachers in Region XII based on pedagogical content knowledge, continuing professional development, and teachers' attitudes toward science. This study used a stratified sampling technique to choose 400 respondents, a quantitative non-experimental causal research design, and mean, Pearson r, multiple regression, and structural equation model (SEM) as statistical tools. Survey questionnaires were deployed to the respondents using the online Google Form. Results revealed that the level of pedagogical content knowledge was very high, the level of continuing professional development was high, the level of attitude toward science was high, and the level of science curriculum implementation was very high. Moreover, pedagogical content knowledge, continuing professional development, and attitude toward science exhibited a significant relationship with science curriculum implementation. Furthermore, pedagogical content knowledge was the domain that best influences science curriculum implementation. Finally, among the five generated models, Model 5 best-fitted science curriculum implementation with pedagogical content knowledge in terms of subject matter knowledge, instructional objective and context, and knowledge of students' understanding, continuing professional development in terms of updating, reflective, and collaborative activities, and attitude toward science in terms of perceived dependency on context factors, self-efficacy, the difficulty of science teaching, and perceived relevance.