Teachers' teaching practices are influenced by various factors, including the teacher's personal (e.g. beliefs, efficacy and attitudes) and school context (e.g. administrative and collegial support). However, the previous model did not consider the interactions between these factors simultaneously in effecting the teaching practices. Thus, an integrated model is needed to gain a better understanding of teachers' teaching practices. This study proposes a structural equation model by integrating beliefs (constructivist conception of teaching and learning) (CC), self-efficacy in integrated STEM teaching (SE), attitudes towards integrated STEM teaching (ATT) and school context (CF) in predicting science teachers' integrated STEM teaching practices (TP). The results of a cross-sectional survey of 333 science teachers show that desired improvements in the CC, SE, ATT and CF may result in corresponding changes in the TP. The effects of CC on TP are fully mediated by ATT, while SE affects TP both directly and indirectly via ATT. The results of the study provide a theoretical base for prospective researchers involved in exploring integrated STEM training or other active learning practices.