Thorough knowledge of retroperitoneal anatomy is very important to a gynecology oncology surgeon. Primary retroperitoneal structures are abdominal aorta, inferior venacava, adrenal gland, kidneys and the ureter. Bladder and rectum are pelvic retroperitoneal organs. Secondary retroperitoneal organs are the head and neck of pancreas, second and third part of duodenum and ascending and descending colon. Intra abdominal aorta runs to the left of midline and inferior venacava (IVC) to right of midline. After having given seven paired side branches and 3 midline branches aorta divides into common iliac arteries at the lower border of L4 vertebra. Cisterna chyli is situated on L1 and L2 vertebrae; azygos vein arises from left renal vein; hemiazygos from IVC. All the above structures, depend on destination enter or leave the abdomen through named hiatuses in diaphragm. Quadratus lumborum, Pectoralis Major, and Iliacus form the major part of posterior abdominal wall. Nodal groups in retroperitoneum are discussed with descriptive and practical nodal grouping systems. Ureteric anatomy, nerves of posterior abdominal wall and secondary abdominal retroperitoneal organs are also discussed in detail.