Three cases of perineal eventration after amputation of rectum are reported. Defined as the issue of intraperitoneal contents at the perineum secondary to surgery, perineal eventration occurs after 1% of abdominoperineal amputations, more frequently in women. Predisposing factors are a wide pelvis, extensive excision of levator muscles, hysterectomy, factors of postoperative increased abdominal pressure, absence of postoperative adhesions between intestinal loops and infection of perineal scar. The influence of primary or secondary wound closure is more difficult to determine. The eventration is manifest by pain and perineal bulging, sometimes marked and preventing walking, but asymptomatic forms are frequent. Intestinal loops are visible below a thinned skin, cutaneous ulcers, urinary disorders and rupture of sac being the common complications. Surgical treatment is necessary for patients free from neoplastic recurrence, those inconvenienced by the eventration and those with large eventrations, the most effective procedure being uterine fixation to promontory, and use of a plate to close lower region of pelvis, using an abdominal approach alone.