Hypertrophy in capillary malformation (CM) may be present at birth or manifest itself later in life. To gain insight into the pathology of hypertrophic CM, we investigated a series of 11 excisional biopsies of hypertrophic lips.All biopsies showed dilated thin-walled microvessels in the superficial dermis without a neural component. However, large multinodular conglomerates of thick-walled vessels with a substantial increase in nerve fibers were found in the deeper parts of the lesions. These veins extended deep into the facial musculature. Hypertrophy in CM is caused by venous malformation underlying the CM. So CM associated with hypertrophy should be considered as Capillary Venous malformations.