Enterocolic lymphocytic phlebitis (ELP) is a rare disease of unknown etiology involving most often the intramural and mesenteric small and medium-sized veins of the gastrointestinal tract. The diagnosis of the disorder is based on the histopathological examination of a surgical specimen as endoscopically obtained diagnostic material is usually too superficial. Clinical manifestation of ELP most frequently is characterized by acute symptoms, such as acute abdomen, signs suggesting acute appendicitis, gastrointestinal hemorrhage, sometimes it manifests as chronic gastrointestinal complaints. We report, to our knowledge for the first time in Poland, a case of ELP with clinical symptoms pointing to acute appendicitis, on laparoscopy manifesting as a tumorous mass in the colonic wall with an unchanged appendix.