Disorders of sex development (DSD) represent a spectrum of conditions in which chromosomal, gonadal, or anatomic sex are atypical and affect 1 in 4,500-5,000 live births. The diagnosis of DSD raises concerns of tumor risk and treatment as well as future fertility preservation. We review the current understanding of the types of gonadal tumors that arise in DSD patients as well as possible markers and treatment. The goal is to inform the members of the DSD team (urologist, endocrinologist, geneticist, psychologist) of the latest findings regarding malignancy in DSD. PubMed® and Google ScholarTM literature searches were performed of current and past peer-reviewed literature on DSD (intersex) regarding gonadal development and tumor formation/treatment. Relevant reviews and original research articles were examined, including cited references, and a synopsis of the data was generated. DSD patients are at increased risk for the development of testicular carcinoma in-situ (CIS) and germ cell tumors (GCT), including seminoma, non-seminoma, juvenile granulosa cell, gonadoblastoma, and dysgerminoma. Cancer risk factors include Y-chromosomal material and gonadal position, especially for streak gonads. The 46 XX DSD patients [congenital adrenal hyperplasia (CAH)] with no genetic Y-chromosomal material are not at higher risk of cancer. Post-pubertal complete androgen insensitivity syndrome (AIS) patients remain prone to tumor development if the testes remain in the abdomen. Estimates of the risk of GCT in partial AIS for untreated undescended testes may be as high as 50%. The cancer risk of scrotal testes in partial AIS is unknown. CIS occurs almost exclusively in patients with hypovirilization, most notably in AIS. Persistent Mullerian Duct Syndrome (PMDS) confers the usual cancer risk associated with cryptorchidism, but also a possible tumor risk of the Mullerian remnant. Several markers are under investigation for tumor evaluation in the DSD population beyond hCG and AFP (Oct3/4, TSPY, WT-1). The management of patients with DSD is complex and evaluation of tumor risk is aided by advances in genotyping for Y-chromosomal material not evident in traditional karyotyping. More complete genetic screening for DSD patients should increasingly become the standard of care. Developments in pathologic diagnosis will further challenge our traditional understanding of the oncologic management and surveillance of these patients. Future studies utilizing more advanced histologic examination of gonads will improve our understanding of the true incidences of malignancy in this diverse population.