Purpose
This study involved using teaching styles, professional developments of teachers and organizational cultures of schools as independent variables and investigating the effects of these two factors on teachers’ teaching effectiveness. Additional analysis was conducted regarding the moderating effects of organizational cultures of schools as well as the mediating effects of teachers’ professional developments.

Design/methodology/approach
A total of 400 teachers at 30 high schools in Taichung City were investigated through teacher self-assessment; the employed questionnaires covered teaching styles, professional developments, organizational cultures of schools, and teachers’ teaching effectiveness and contained four subscales. Hierarchical linear model (HLM) was used to analyze the relationships among variables.

Findings/results
Teaching styles exert effects on the dimensions of teachers’ teaching effectiveness; teaching styles exert effects on the dimensions of teachers’ professional developments; teachers’ professional developments exert effects on the dimensions of teachers’ teaching effectiveness. Besides, teaching styles have indirect effects on teachers’ teaching effectiveness through the different mediating effects of teachers’ professional developments. Furthermore, organizational cultures of schools have effects on teachers’ teaching effectiveness; organizational cultures of schools serve as the moderator between teaching styles and teachers’ teaching effectiveness.

Originality/Value
In the past few studies, teachers’ teaching styles, teachers’ professional developments, and teachers’ teaching effectiveness were rarely discussed together, let alone analyzing teachers’ professional developments as a mediating variable. In addition, the relationship among these factors is rarely examined from the integrated perspective. Therefore, this study analyzed the effects of organizational cultures of schools on the relationship between teachers’ teaching styles and teaching effectiveness from a multilevel perspective.

Suggestions/implications
Based on the research results, this study proposes some discussions and suggestions that schools should strengthen high school teachers’ cognition of teachers’ teaching style, promote the professional development of teachers and create a good school organizational culture so as to enhance teachers’ teaching effectiveness. Finally, this study proposes some suggestions to the further future study.