Abstract: Ovarian cancer is a common gynecologic malignancy. In clinical practice, recurrent ovarian cancer is mainly classified into two categories on the basis of platinum-free interval, platinum-resistant and platinum-sensitive, corresponding to different treatment modalities and prognoses. The treatment of platinum-resistant ovarian cancer is challenging. Some scholars have pointed out limitations in the binary classification of platinum-free interval. In this article, the classification of recurrent ovarian cancer, the treatment challenges of platinum-resistant ovarian cancer, the limitations of the platinum-free interval binary classification, and new classification perspectives were reviewed to help physicians enhance their understanding on the research progress in ovarian cancer classification and develop more effective treatment strategies.