The transversalis fascia (or transverse fascia) is the fascial lining of the anterolateral abdominal wall^[1][2] situated between the inner surface of the transverse abdominal muscle, and the preperitoneal fascia.^[3][2] It is directly continuous with the iliac fascia,^[2] the internal spermatic fascia,^{[citation needed]} and pelvic fascia.^[2]

In the inguinal region, the transversalis fascia is thick and dense; here, it is joined by fibers of the aponeurosis of the transverse abdominal muscle. It becomes thin towards to the diaphragm, blending with the fascia covering the inferior surface of the diaphragm.^[2]

Posteriorly, it is lost in the fat which covers the posterior surfaces of the kidneys^{[clarification needed][2]}

Below, it has the following attachments: posteriorly, to the whole length of the iliac crest, between the attachments of the transverse abdominal and Iliacus; between the anterior superior iliac spine and the femoral vessels it is connected to the posterior margin of the inguinal ligament, and is there continuous with the iliac fascia.^[2]

Medial to the femoral vessels it is thin and attached to the pubis and pectineal line, behind the inguinal falx, with which it is united; it descends in front of the femoral vessels to form the anterior wall of the femoral sheath.^[2]

Beneath the inguinal ligament it is strengthened by a band of fibrous tissue, which is only loosely connected to the ligament, and is specialized as the iliopubic tract.^[2]

• Transversalis fascia
• Diagram of sheath of rectus.
• Diagram of a transverse section through the anterior abdominal wall, below the linea semicircularis.
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