Klippel-Trenaunay综合征(KTS)又称先天性静脉畸形骨肥大综合征,好发于儿童及青少年。临床以多发性皮肤血管瘤、肢体静脉曲张、骨及软组织肥大为特征。其病因尚不清楚,可能为遗传性血管壁间质组织发育异常所致。目前尚无特异的治疗方法,手术及介入治疗主要是减轻症状和治疗并发症。对于婴儿期出现偏侧肢体肥大并血管瘤的患儿应长期随访,早期诊断,早期干预以防止并发症。近年来有报道利用超声进行产前诊断,对及时发现和处理有重要意义。本文报道1例婴儿期KTS,以口腔黏膜血管瘤伴出血、颜面及肢体不对称性肥大为特点,并伴精神运动发育迟缓,CT见侧脑室、三脑室扩张。 Klippel-Trenaunay syndrome (KTS), also known as congenital venous malformations of bone hypertrophy, occurs in children and adolescents. Clinical features of multiple cutaneous hemangiomas, limb varicose veins, bone and soft tissue hypertrophy. The etiology is unclear, may be due to hereditary vascular wall dysplasia. There is no specific treatment, surgery and intervention mainly to reduce symptoms and treatment of complications. For infants with unilateral limb hypertrophy and hemangioma in children should be long-term follow-up, early diagnosis, early intervention to prevent complications. In recent years, it has been reported that the use of ultrasound for prenatal diagnosis, timely detection and treatment is of great significance. This article reports a case of infantile KTS, with oral mucosal hemangioma with bleeding, facial and limb asymmetry hypertrophy is characterized by mental retardation, CT see the lateral ventricle, third ventricle dilatation.