The purposes of the present study are to: (a) describe the beliefs and practices of the US and Taiwan (TW) public and private kindergarten teachers regarding developmentally appropriate practice (DAP), (b) examine the group differences between the four groups of teachers, and (c) identify the salient factors related to the variability of developmentally appropriate beliefs and practice in these teachers. Three hundred and fifty-seven kindergarten teachers participated in the study. The group sizes were 123, 123, 57, and 54 for Taiwan private, Taiwan public, US private, and US public kindergarten teachers, respectively. A survey was used to collect data. Findings from this study showed: (a) Both the US and Taiwan kindergarten teachers highly endorsed beliefs about DAP; (b) US and Taiwan kindergarten teachers also held strong beliefs about developmentally inappropriate practices (DIP); (c) DAP activities occurred regularly in the classrooms; (d) developmentally inappropriate practice (DIP) activities also took place a lot although they were lower than the DAP activities; (e) the Taiwan teachers had higher beliefs about DAP and lower beliefs about DIP than the US teachers; (f) the US teachers reported both higher DAP and DIP activities than the Taiwan teachers; (g) there were no differences between public and private kindergarten teachers; (h) hierarchical regression analyses using teacher's personal demographic variables as the first block and numbers of boys and girls as the second block were generally not effective; (i) there were different sets of best predictors from the backward regression for different dimensions of developmentally appropriate beliefs and practices; and (j) beliefs about DAP and DIP were usually more powerful than the demographic and classroom variables in predicting the DAP and DIP activities. Future studies are needed to refine the Teacher Belief Scale and Instructional Activity Scale instruments and include classroom observations to verify and expand the findings. Future teacher training on DAP should promote beliefs about DAP and reduce beliefs about DIP. Enhancing teachers' skills to implement the DAP activities and decrease the DIP activities is suggested.