Ultrasound is a helpful imaging tool for triaging and in most instances making a definitive diagnosis of abnormalities of the fetal and neonatal genitourinary systems. Ultrasound can define an abnormality found in a fetus or neonate as definitively related to the genitourinary system, guiding further workups. Ultrasound can be used to assuage clinical concern by showing normal anatomic findings or variants that can simulate abnormality. This article discusses necessary information to aid in ultrasound diagnosis in various areas of the perinatal genitourinary system including the kidneys, bladder, and genital system. It discusses some adrenal findings that may help in these diagnoses.