目的　探讨儿童扩张性心肌病的临床特点及基因特征。方法　分析1例儿童扩张性心肌病患儿的临床资料 和基因检测结果，并复习相关文献。结果　男性患儿，11岁，活动后气促、心悸，心脏彩超提示左心室、左心房明显扩大， 左室射血分数35%，左室短缩分数20%。基因检测结果显示，患儿及母亲RBM20基因9号外显子出现杂合突变c.2264G > A，p.Arg755His，11号外显子也出现杂合突变c.3014A > G，p.Asp1005Gly，均为错义突变，以前均未见报道。结论　儿童 家族性扩张性心肌病诊断主要通过临床和基因检测。

Objective　To explore the clinical and gene characteristics of dilated cardiomyopathy in children. Method　The clinical data and gene test results of dilated cardiomyopathy in a child were analyzed and the relevant literatures were reviewed. Results　There was an 11-year-old male patient who had shortness of breath and palpitation after exercise. Color Doppler echocardiography showed enlarged left ventricle and left atrium, with left ventricular ejection fraction at 35% and left ventricular shortening fraction at 20%. The results of genetic testing found heterozygous mutations, c.2264G > A, p.Arg755His in exon 9 and c.3014A > G, p.Asp1005Gly in exon 11 of RBM20 gene in both child and mother. They were missing mutations and had not been reported before. Conclusion　The diagnosis of familial dilated cardiomyopathy in children is mainly based on clinical and genetic testing.