Objective　To observe the effect of Radix astragali (RA) on myocardial connexin-43 in rats with dilated cardiomyopathy (DCM). Methods The dilated cardiomyopathy model in rat was established through intraperitoneal injection with adriamycin. The rats in the model group were randomly divided into RA group and the model control group according to different methods of administration. Rats in RA group were gavaged with Astragalus particles and double-distilled water, and rats in model control group and normal control group were gavaged with an equal amount of double-distilled water daily for four weeks. At the end of 12 weeks, the left ventricular ejection fraction (LVEF) was measured with echocardiogram. The Cx43 mRNA level was tested by reverse transcriptase polymerase chain reaction (RT-PCR). Immunohistochemical method was used to observe myocardial Cx43 expression and distribution. Results Compared with the model control group, the Cx43 mRNA and protein expressions and LVEF were increased significantly in RA group (P<0.05). The disorders in distribution of myocardial Cx43 improved in RA group in contrast to the model control group. Conclusions Radix astragali can improve myocardial Cx43 expression and distribution in DCM rats, and can further improve the cardiac function.