Critical thinking of students is needed in 21st century learning, the fact is the acquisition in the field is still low. Therefore this study aims to improve students' critical thinking skills using the inquiry model assisted with the ethnoconstructivism module. Methodology uses a quantitative design of a quasi-experimental pretest-posttest non-equivalent control group design with a total sample of 64 students taken by purposive sampling technique. There were significant differences in terms of students' critical thinking between the control class and the experimental class. It can be underlined that the inquiry model with ethnoconstructivism has a significant influence on the way students think about cultural values compared to traditional groups.