The purpose of this study is to determine the critical thinking ability of preservice science teachers. Also the interchangeability of learning styles in their level of critical thinking ability is also studied. The study was done through survey method. The research was held in 2014-2015 fall semester Faculty of Education Science Teaching Program 1st, 2nd, 3rd, 4th grade students -120 students in total. As a data collection tools, California Critical Thinking Skills Scale and Kolb Learning Style Inventory developed by Kolb [1] were used in this study. In the analyses of the datum, it will be used to descriptive statistics, independent t test, one-way ANOVA. The research data were collected.