Abstract： Objective To analyze the clinicopathologic features of hereditary cutaneomucosal venous malformation (VMCM) in a Chinese family.Methods Family history was investigated in a family with VMCM,and tissue specimens were obtained from the lesions of the proband and subjected to histopathological analysis.Results Among 65 members from 5 generations of the family,19 were affected by VMCM,hinting an autosomal dominant inheritance.None of the family members experienced gastrointestinal bleeding,central nervous system disorders,or cardiac defects.Affected individuals usually presented with multiple irregularly sized,blue-violet,elevated and slightly indurated masses located in the oral mucosa and subcutaneous tissue of the extremities.Pathological analysis showed malformed veins with abnormally dilated cavities and irregularly thickened walls.Although small veins were abnormally proliferating and clustered,there was no endothelial discontinuity.The smooth muscle layer was thickned in a varying degree or absent.Conclusion A diagnosis of VMCM is made according to the inheritance manner,clinical manifestation and pathological findings.