目的探讨小儿病毒性心肌炎与自由基的关系。方法测定了６５例病毒性心肌炎患儿血清超氧化物歧化酶活性和脂质过氧化物的终产物丙二醛含量。结果显示急性期与正常组比较超氧化物歧化酶活性明显降低（Ｐ＜００１），丙二醛含量显著升高（Ｐ＜００１）。恢复期与急性期比较超氧化物歧化酶活性明显升高（Ｐ＜００１），丙二醛含量也明显降低（Ｐ＜００１）。而恢复期与正常组比较超氧化物歧化酶变化差异不明显（Ｐ＞００５），丙二醛含量却有明显差异（Ｐ＜００５），但仍未降至正常值。结论表明自由基—脂质过氧化作用在病毒性心肌炎发病中起一定作用，且与病情轻重和病期长短有一定关系。 Objective To investigate the relationship between viral myocarditis and free radicals in children. Methods Serum levels of superoxide dismutase (SOD) and malondialdehyde (MDA), the final product of lipid peroxides, were measured in 65 children with viral myocarditis. The results showed that the activity of superoxide dismutase in acute phase was significantly lower (P <001) and the content of malondialdehyde was significantly higher (P <001). Compared with the acute phase, the activity of superoxide dismutase (SOD) was significantly increased (P <001) and MDA content was also significantly decreased (P <001). However, there was no significant difference in the changes of superoxide dismutase between the recovery phase and the normal group (P> 005), and the content of malondialdehyde was significantly different (P <005), but still not reduced to normal. Conclusions show that free radical - lipid peroxidation plays a role in the pathogenesis of viral myocarditis, and with the severity and duration of a certain relationship.