患者女，19岁，3年前发现左前臂青紫色且逐渐增大包块，无明显疼痛，活动度可，按压时青紫色消失，初诊为左前臂静脉畸形。采用手术治疗，术中见瘤体边界清，包膜完整，瘤体血运十分丰富，内含较多超微毛细血管网，大体观似静脉畸形。经病理检查诊断为皮下错构瘤。术前、术中的临床表现与静脉畸形十分相似导致误诊，因此遇到类似疾病，应慎重处理，拓宽对疾病的分析思路。“,”The patient, a 19-year-old female, found that the blue and purple mass was in her left forearm 3 years ago, and the mass gradually increased without obvious pain. It disappeared when pressing. The first diagnosis was “left forearm venous malformation” . During the operation, the boundary of the tumor body was clear and the capsule was complete. The blood supply of the tumor body was very rich. There were many micro capillary networks in the tumor body. It looked like “venous malformation” by general observation. But it was diagnosed as subcutaneous hamartoma by pathological examination. It was very similar to venous malformations by preoperative and intraoperative clinical manifestations, which will lead to misdiagnosis. Therefore, we should carefully handle and broaden the thinking of disease analysis in the similar cases.