Objective This study aimed to assess the cardiac function injury in SD rats induced by Camrelizumab using a combination of ultrasonic diagnosis and serum biochemical indexes.Methods A total of 32 female SPF SD rats, aged 8-9 weeks, were selected to establish a breast cancer rat model through subcutaneous injection of MADB-106 rat breast cancer cells in the right groin area. The rats were randomly divided into four groups (control group, standard dose group, medium dose group, and high dose group), with eight rats in each group. Rats in the standard dose group, medium dose group, and high dose group were successively injected with 5 mg, 10 mg, and 20 mg of Camrelizumab (dissolved in 0.5 ml PBS buffer), respectively. Rats in the control group received intraperitoneal injections of the same amount of PBS buffer for six consecutive times at intervals of 20 days between each injection from 17:00 to 20:00 on the same day. Cardiac function parameters including left ventricular ejection fraction (LVEF), left ventricular brachyaxis shortening rate (FS), and Tei index were evaluated using ultrasonography. After ultrasound examination, blood samples ranging from 2 to 10 ml were collected under cardiac negative pressure during anesthesia to measure interleukin-6 (IL-6) concentration, tumor necrosis factor-alpha (TNF-α) concentration, brain natriuretic peptide precursor (NT-proBNP) concentration and programmed death receptor-1(PD-1) antibody level. The above parameters were compared before and after experimental treatment within each group. After blood collection, the rats were immediately dissected for calculation of heart organ coefficients for comparison purposes..Results All SD rats survived and had a tumor formation rate of 100%. There were no significant differences observed in LVEF , FS ,and Tei indexes between pre-treatment measurements and post-treatment measurements within control groups as well as standard-dose groups or medium-dose groups . However, in high-dose groups, LVEF decreased, Fs decreased, and Tei index in control group, standard dose group and medium dose group before and after treatment. Compared with before experimental medication, LVEF and FS were decreased and Tei index was increased in high-dose group after experimental medication, with statistical significance (all P < 0.05). Compared with control group, medium dose group and standard dose group, LVEF and FS were decreased and Tei index was increased in high dose group after experimental treatment, and the differences were statistically significant (all P < 0.05). There was no significant difference in IL-6, TNF-α and NT-proBNP in control group, standard dose group and medium dose group. Compared with control group, standard dose group and medium dose group, IL-6, TNF-α and NT-proBNP in high-dose group were increased after experimental treatment, and the differences were statistically significant (all P < 0.05). Compared with control group, standard dose group and medium dose group, PD-1 antibody in high-dose group was increased after experimental treatment, and the differences were statistically significant (all P < 0.05). There was no significant difference in cardiac organ coefficients among all groups of SD rats.Conclusion After ultrasonic diagnosis and evaluation，combined with the change of serum biochemical ion concentration，Camrelizumab can cause inflammatory response in SD rats，thus damaging myocardial cells in SD rats，leading to cardiac function injury，and promoting the decline of cardiac function and motor function，in a dose-dependent manner，but does not affect the cardiac coefficient.