This article describes the effects of inquiry learning model on college students' cognitive and critical thinking skills. The research aims at understanding the extent inquiry learning model improves the college students' cognitive and critical thinking skills in the lessons of educational philosophy and exploring students' responses to the model. This is a pre-experimental research design, using the one group pretest-posttest design. The samples of the study were an intact class, the experimental group and no control group is needed. The data was analysed using independent test samples t-test and Normalized Gain test. The Research found that the inquiry model is effective in improving college students' cognitive and critical thinking ability in an educational philosophy class. Overall, the N-Gain indicator of cognitive ability increased by an average of 0.66, and the N-Gain indicator of critical thinking skills increased by an average of 0.63.