This study aimed to examine the process of adaptation after the experience of regret, with a focus on regulatory focus as a factor determining regulation strategies for regret, cognitive emotion regulation as a regulation strategy for regret, and preparatory functions of regret. We evaluated a model in which regulatory focus influences cognitive emotion regulation and how it influences preparatory function through regret using a questionnaire survey administered to 430 university students. The results suggest that several processes lead to preparatory functions of regret. For example, there seems to be a process whereby “positive reappraisal,” promoted by promotion focus, reduces regret and enhances preparatory function, and another process whereby several maladaptive strategies promoted by prevention focus increase regret, which facilitates preparatory function. In addition, some maladaptive strategies are strengthened by promotion focus, and some adaptive strategies are associated with prevention focus and increased regret.