The study aimed to adapt Kember scale of reflective thinking to Jordanian context, and to extract the indicators of validity and reliability of the scale, the study sample consisted of (1065) male and female students, namely, (548) male and (517) female students from sixth, eighth and tenth grades from Amman, they were reached by social media after the coordination with school managers and teachers, where the scale was distributed on the social media sites of a number of schools in Amman city. To achieve the aim of this study, the Kember, et al. (2000) scale of reflective thinking has been translated, the scale contains four dimensions: Habitual behavior, understanding, reflection, and critical reflection. The indications of validity were extracted through two ways, face validity, and construct validity by calculating Pearson correlation coefficients between the items and the total degree on each dimension, whereas, indicators of reliability were also extracted by means of test re-test, and Cronbach’s Alpha methods. Further, the results showed differences in reflective thinking performance due to students’ academic achievement, whereas, they showed no differences due to gender differences nor grade differences.