The aim of the study was to investigate the mitigative effects of bisoprolol (BIS) in cadmium-induced myocardial toxicity on oxidative stress and its inhibitive effect on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signalling in rats. Male albino Wistar rats were assigned to control, Cd, BIS 2 (2 mg/kg b.w.) and BIS 8 (8 mg/kg b.w.) groups with nine rats in each. Over four weeks, the control group was administered 1% gum acacia, all other groups received 3mg/kg b.w. CdCl₂ dissolved in distilled water, and the BIS groups were additionally given bisoprolol in gum acacia. Blood samples were collected for biochemical estimations. Blood pressure and serum biomarker (lactate dehydrogenase, aspirate transaminase, alanine transferase and creatine kinase-MB, enzyme (superoxide dismutase, lipid hydroxy peroxidase, catalase and malondialdehyde), and tumour necrosis factor alpha (TNF-α) concentrations were measured. Western blot analysis was conducted for NF-κB and glutathione S-transferase (GST). After sacrificing the rats, cardiac tissue samples were examined histopathologically. Our findings pointed to a significant decrease (P < 0.05) in the studied serum biomarkers and levels of the relevant enzymes in the BIS 8 group compared to the Cd group. A significant decrease (P < 0.05) in NF-kB p65 expression and TNF-α levels was noted in the BIS 8 group relative to the BIS 2 and Cd groups, indicating a reduction at a higher dose. In microscopy, histopathological changes in the cardiac muscles of the BIS 8 group were evident compared to those of the Cd group. BIS seemed to have protective effects against cardiac injury induced by cadmium and could be considered a novel therapeutic drug and prognostic biomarker in the pathology of the many cardiovascular diseases caused by heavy metal intake.