The developmentally appropriate practice (DAP) guideline offers professional standards for high quality practice in early childhood education in the United States and abroad. The present study examines how well the three aspects of teacher efficacy beliefs including self-efficacy for teaching, self-efficacy for parent involvement, and general teaching efficacy predict teacher beliefs about DAP as well as developmentally inappropriate practice (DIP) through structural equation modeling. The sample comprised 251 preschool teachers employed in public pre-primary schools in a metropolitan city in Turkey. Results indicated that general teaching efficacy was a significant predictor of teacher beliefs about DAP and DIP. Teacher self-efficacy for parent involvement significantly predicted teacher beliefs about DAP but not DIP. There was not any significant influence of teacher self-efficacy for teaching on teacher beliefs about DAP and DIP. This study overall suggests that teacher efficacy beliefs constitute one of the important sources of teacher beliefs about DAP.