Defects of decision-making play an important role in cognitive dysfunction of obsessivecompulsive disorder （OCD）. Researching decision making function of OCD is very meaningful， which can not only improve further understanding of OCD， but also provide valuable references for future clinical treatment. The main research theories and research results of decision making function of OCD are reviewed in this article， which is divided into four parts： risk preference theory， goal-oriented theory， evidence accumulation theory and metacognition theory.