This study aimed to determine the effect of learning with reversible problem-solving approach on prospective-math-teacher students' reversible thinking. Using experimental research design, the study involved 65 prospective math teacher students as respondents (35 experimental, 30 control). Experimental class implemented a learning with reversible problem-solving approach as the treatment; thing the control class would not do so. A post-test on reversible thinking was applied to both classes for data collection of the students' reversible thinking, and it was further analyzed using t-test via SPSS 23. The result found that the mean score of experimental class was 76.7143, while the control class was 35.3333. A significant difference between their mean score was evident. Hence, it indicated that the post-test of experimental class was considered better than the control one. This post-test result was further analyzed using equal variance assumed t-test via SPSS 23. Result showed that there was a significant difference between both classes on their post-test score. Thus, the study established that learning with reversible problem-solving approach definitely brought effect on prospective-math-teacher students' reversible thinking ability. The effect was significant and positive.