Objective: To assess CT findings of pyourachus. Materials and Methods: Computed tomography of two patients with surgically proven pyourachus was reviewed. Results: The CT characteristics of pyourachus include (a) midline location deep to the rectus abdominis muscle; (b) conical shape extending from a tip at the umbilicus to a base over the bladder dome; (c) peripheral inflammatory changes in subcutaneous tissues, rectus abdominis muscle, and mesenteric fat; and (d) intraperitoneal fluid or abscess (if perforation has occurred). Conclusion: Abdominal CT demonstrates characteristic findings in pyourachus that should allow differentiation from other abdominal-pelvic masses.