The paraaortic lymph nodes (also para-aortic, periaortic, and peri-aortic) are a group of lymph nodes that lie in front of the lumbar vertebral bodies near the aorta. These lymph nodes receive drainage from the lower gastrointestinal tract and the pelvic organs.

The paraaortic lymph node group is divided into three subgroups: preaortic, retroaortic, and right and left lateral aortic. The preaortic group drains the abdominal part of the gastrointestinal tract above the mid-rectum. The lateral group drains the iliac lymph nodes , the ovaries, and other pelvic organs. The lateral group nodes are located adjacent to the aorta, anterior to the spine, extending laterally to the edge of the psoas major muscles , and superiorly to the crura of the diaphragm.

When a paraaortic lymph node dissection or sampling is done as a part of the treatment of cancer, the lateral aortic lymph node group is the most important group. There are typically 15 to 20 lymph nodes on each side. When dissected, the dissection usually includes the region from the bifurcation of the aorta to the superior mesenteric artery or the renal veins.