The vascular type of Ehlers-Danlos syndrome (type IV) is an infrequent disease caused by heterozygous germline mutations in the procollagen 3A gene (COL3A1). Clinical signs include characteristic facial features, easy bruising, and a translucent skin. These signs are less obvious than the hyperflexibility of skin and joints seen in other types of Ehlers-Danlos syndrome. Therefore, diagnosis of Ehlers-Danlos syndrome type IV is usually not considered until complications have occurred. Complications include spontaneous ruptures of vessels and hollow organs, particularly the colon. We, herein, report pathologic findings in colon specimens from related Ehlers-Danlos syndrome type IV patients. Thorough examination revealed abnormalities of the large bowel architecture including abrupt changes in the caliber of the lamina muscularis, secondary diverticula formation, and strongly reduced expression of abnormal collagen 3. These findings are not seen in other diseases of the colon and should prompt the pathologist to include Ehlers-Danlos syndrome type IV in the differential diagnosis of spontaneous bowel perforation in younger patients.