This study intended to clarify the realities of critical thinking of high school students in science learning. A 42-question survey was conducted on 231 1st-year high school students to achieve this end. The results indicated while students have a strong curiosity about phenomena and emphasize objective opinions and ideas, they also draw conclusions even in the absence of the necessary experimental data and interpret results without confirming whether there are conditions that have been overlooked. In addition, the causal relationship of “the more an inquisitive the student, whether they be a student of the humanities or sciences, the more importance they place on validity and reproducibility even when they know the rules or even in experiments where the results can be predicted” was also clarified as a factor structure that influences the critical thinking of students. At the same time, the causal relationship of “the more an inquisitive the student and the more they objectively judge their own ideas and the ideas of others, the more they carefully collect and interpret experimental data” was also clarified.