Vascular pathology of the greater omentum is still being very rare, since Bush described the first case in 1896. The objectives are to describe two clinical cases, the first one about right-sided segmental torsion of the greater omentum and the other one about infarction of the greater omentum, which were diagnosed and treated in our hospital; as well as to check pertinent literature. In first case, a forty year old male, thin, with one week evolution: right lower quadrant pain, nausea, hiporexia, a previous prescription of an antiamebic and antispasmodic with no healing, fever, mild leukocytosis, neutrophilia, simple X ray of the abdomen suggesting acute appendicitis. The patient underwent exploratory laparotomy revealed right-sided segmental torsion of the greater omentum. In second case, a thirty year old female, thin, presenting a six day evolution: pain in the whole right hemiabdomen, difficulty for walking, abdominal distention, hiporexia, fever, bad general condition, with a previous prescription based on metamizol, ampicilin with no healing, mild leukocytosis, neutrophilia and simple X-ray of the abdomen also suggesting acute appendicitis. This patient was also surgically treated with the diagnosis of right-sided segmental infarction of the greater omentum. In conclusion, vascular pathology of the greater omentum is still being very rare. Its clinical presentation is nonspecific and forms a great part of pathology which causes right lower quadrant pain, commonly confused with acute appendicitis. Despite medical breakthrough its diagnosis is difficult. The treatment is surgical, evolution is good if the treatment is adequate, and prognosis is favorable.