Ovarian germ cell tumors (OGCTs) account for approximately 30% of all primary ovarian neoplasia, secondary only to epithelial ovarian tumors in prevalence. OGCTs occur mostly in younger women, constituting approximately 60% of all ovarian tumors in individuals under 21 years of age. The majority of OGCTs are pure, while about 10% of OGCTs exhibit mixed components. In such mixed tumors, the behavior and prognosis are primarily determined by the most malignant component. Hence, meticulous examination and comprehensive specimen sampling are imperative to identify and quantify all tumor components. Germ cell tumors generally mimic various stages of normal embryogenesis and possess the potential to develop into any normal tissue type. However, the haphazard distributions and diverse composition of tissue types within OGCTs can pose diagnostic challenges. Achieving the correct diagnosis depends on familiarity with this potentially haphazard pattern of various tissue types, precise identification of all tissue components, and recognition of foci suggestive of malignant transformation. This chapter focuses on the clinicopathologic characteristics of OGCTs and also briefly covers mixed germ cell and sex cord-stromal tumors.