This study examined the strategies participants used to make preference choices in past temporal discounting tasks. The research participants included 33 healthy Chinese college students. Ten past temporal distances, from two weeks to 50 years, were chosen. After completing the experiment task in the delay paradigm, a questionnaire survey assessed the strategies participants used to make preference decisions. This study examined the strategies participants used to make preference choices in past temporal discounting tasks. The subjects included 33 college students. Ten past temporal distances, from two weeks to 50 years, were chosen. After completing the experiment task in the delay paradigm, a questionnaire survey assessed the strategies participants used to make preference decisions. Indifference points were calculated into the rate of past temporal discounting using UAUr(t1,t2). The content analysis of the questionnaire responses revealed that the anticipated benefit of past rewards in the present contributed to the changed rate of past temporal discounting, which caused the dominant strategies to change with increasing past temporal distance.