The spleen is the largest organ of the human lymphatic system. It is located in the left upper quadrant (or the left hypochondrium) of the abdomen, as it usually lies against the diaphragm in the area of the ribs 9 to 11.

The spleen is related to other organs of the abdominal cavity. It is connected to the greater curvature of the stomach by the gastrosplenic ligament, which contains short gastric and left gastro-omental vessels. It is also related to the left kidney by the splenorenal ligament, which contains the splenic vessels. Both mentioned ligaments arise from the greater omentum.

The visceral peritoneum surrounds the spleen, except in the hilum area on the medial surface of the spleen.

The splenic hilum is the entry point into the spleen for the splenic vessels. Also, the tail of the pancreas may reach this area.

The arterial blood supply to the spleen is provided by the splenic artery arising from the coeliac trunk.