A case of a young male with the Klippel-Trénaunay-Weber syndrome is described. Typical features of hemihypertrophy, hemangiomata, macrodactyly, and macrocephaly were present. The most striking oral feature was generalized severe gingival hypertrophy confirmed histologically, ultrastructurally, and by collagen analysis. In the absence of other known systemic causes of gingival enlargement, a diagnosis of familial gingival fibromatosis in association with Klippel-Trénaunay-Weber-syndrome is concluded. The combination of gingival fibromatosis and Klippel-Trénaunay-Weber syndrome has not been reported to our knowledge, it is uncertain whether this occurrence is significant or coincidental.