Ovarian cancer is the second most common gynecologic malignancy, but the most common leading cause of death among gynecologic malignancies. The reason for poor prognosis is largely because there are no obvious sign or symptom in the early stage. Although early manifestation through hormonal activity can be present in case of sex-cord stromal tumors, epithelial tumors (the most common ovarian tumor) rarely have hormonal activity, and the clinical symptom such as a palpable pelvic mass or abdominal distension occurs after the development of advanced stage. In this chapter, we review the general considerations of ovarian cancer, including its classification, staging, and mode of the spread, and discuss the role of imaging in pretreatment evaluation of ovarian cancer. We also discuss the role of cross-sectional imaging in the follow-up of women with ovarian cancer and illustrate variable imaging features of recurrent ovarian cancer.