Obesity is a major worldwide health problem affecting one billion people. The purported cardioprotective benefits of hawthorn against cardiovascular diseases (CVDs) are controversial and may be attributed to its antioxidant and anti-inflammatory properties. The current study explored the underlying protective mechanisms of hawthorn berry extract (HBE) against obesity-induced cardiac injury in rats. The control group (G1) was fed a regular rat diet ad libitum. An obesity-induced cardiac injury model was established by feeding a high-fat diet (HFD) to rats of group 2 (G2) and group 3 (G3), while rats of G3 and group 4 (G4) received oral doses of HBE (100 mg/kg) for ten weeks. A light microscope was used to estimate the morphological changes in cardiac tissues. The apoptosis and ROS values of cardiomyocytes were estimated using flow cytometry. Also, the antioxidant enzymes, lipid profile, proinflammatory cytokines, and cardiac enzymes were assessed. Feeding of G2 with HFD significantly increased rats' body weight, cardiac inflammation, apoptosis, and fibrosis compared to G1. As well, significant oxidative stress was observed by reducing GPx1, SOD3, CAT, and HDL-C with a substantial increase of TG, TC, LDL-C, IL-1β, IL-6, TNF-α, cTnI, cTnT, and CK-MB serum levels. On the contrary, supplementation of G3 with HBE significantly protected rats against all mentioned changes compared to G2. The current study confirmed several mechanisms of obesity-induced cardiac injury and the tremendous cardioprotective antioxidant, hypolipidemic, anti-inflammatory, antiapoptotic, and antifibrotic impact of HBE against obesity-induced cardiac injury. Therefore, hawthorn could provide a novel dietary supplement against obesity-induced cardiac injury.