ObjectiveTo evaluate the effect of Shengmaisan granules on myocardial fibrosis in chronic heart failure patients with Qi-Yin deficiency syndrome by cardiac magnetic resonance （CMR） imaging and serological indicators. MethodSixty-six chronic heart failure patients with Qi-Yin deficiency syndrome who visited the Affiliated Hospital of Integrated Traditional Chinese and Western Medicine， Nanjing University of Chinese Medicine from October 2021 to January 2023 were selected. The patients were assigned into a control group （33 cases） and an observation group （33 cases） by the minimization random method. Both groups received standardized Western medicine treatment for heart failure. In addition， the control group was treated with placebo granules， and the observation group with Shengmaisan granules for a course of 6 months. The baseline data， clinical efficacy， TCM symptom scores， serological indicators ［high-sensitivity C-reactive protein （hs-CRP）， soluble growth stimulation expressed gene 2 protein （sST2）， pro-collagen Ⅲ N-terminal peptide （PⅢNP）， interleukin （IL）-6， IL-11， transforming growth factor-β₁ （TGF-β₁）］， echocardiography ［Left atrial diameter （LAD）， left ventricular end systolic diameter （LVEDs）， left ventricular end diastolic diameter （LVEDd）］ and CMR indicators ［left ventricular ejection fraction （LVEF）， myocardial extracellular volume fraction （ECV）， and longitudinal relaxation time （T1）］ were compared between the two groups. ResultFinally， 31 patients in the control group and 30 patients in the observation group were included. There was no significant difference in baseline data or indicators between the two groups before treatment. Compared with those before treatment， the scores of TCM symptoms （shortness of breath， fatigue， palpitations， spontaneous or night sweats， thirst/dry throat， feverish feeling in palms and soles， and edema in lower limbs）， total score of TCM symptoms， ECV， T1， inflammation/fibrosis indicators （hs-CRP， sST2， PⅢNP， IL-6， IL-11， and TGF-β₁） in observation group decreased （P<0.05， P<0.01）， and the scores of TCM symptoms （except feverish feeling in palms and soles）， T1， and inflammation/fibrosis indicators in the control group decreased （P<0.05， P<0.01）. After treatment， the observation group had lower scores of TCM symptoms （except feverish feeling in palms and soles and edema in lower limbs）， ECV， T1， and inflammation/fibrosis indicators than the control group （P<0.05， P<0.01）. After treatment， the total response rate in the observation group was 93.33% （28/30）， which was higher than that （80.65%， 25/31） in the control group （Z=2.976， P<0.01）. There was no significant difference in adverse reactions between the two groups during treatment. ConclusionFor patients with chronic heart failure with Qi-Yin deficiency syndrome， Shengmaisan Granules can alleviate the TCM symptoms， reduce inflammation， and inhibit myocardial fibrosis by regulating the TGF-β₁/IL-11 signaling axis.