The abdominal wall does not comprise a distinct organ, and is often cursorily evaluated on CT. However, it is affected by many different pathological processes. These may be categorized according to their underlying etiology—trauma, infection or inflammation, iatrogenic and neoplastic process—or according to the abdominal wall layer they affect. We chose instead to group these lesions into 6 distinct categories based on their CT characteristic density: solid, infiltrative, hypervascular, fluid, fat, and bone density lesions. We highlight throughout the article the importance of integrating pertinent clinical history to narrow the differential diagnosis.