Cisplatin (cis-diamminedichloroplatinum, CDDP) is an effective DNA alkylating agent used in the treatment of different types of tumors; however, its clinical use is associated with hepato-cardiotoxicity. The current study was designed to assess the potential protective effect of parsley oil (PO) against CDDP-induced hepato-cardiotoxicity. For this purpose, 25 adult male rats were assigned into five groups, each containing five animals. Group I (control) was administered saline solution. Group II was administered PO at a dosage of 0.42ml/kg BW. Group III were administered CDDP at a dosage of 5mg/kg BW. Group IV was administered PO in addition to CDDP. Group V was administered saline solution in addition to CDDP, after which they were administered PO for five days. Oral administration of either saline solution or PO was performed each day for 10days, while administration of CDDP was via a single intraperitoneal injection five days following the commencement of the experiment. The recorded results revealed that CDDP induced obvious hepatic and cardiac injuries that were indicated by biochemical, histopathological, and immunohistochemical alterations, including elevation of serum hepatic and cardiac injury markers as well as proinflammatory cytokines. Moreover, CDDP induced an increase in the level of hepatic and cardiac injury biomarkers, decreases in the activities of antioxidant enzymes, a decrease in GSH concentration, and an increase in MDA concentration. CDDP also induced histopathological hepatocellular and myocardial changes, and overexpression of p53 and COX-2 in hepatic and cardiac tissues. Administration of PO either as a preventative medicine or as treatment significantly improved all the observed deleterious effects induced by CDDP in rat liver and heart. Thus, it may be concluded that PO, with its antioxidant, anti-inflammatory, and antiapoptotic activities, can potentially be used in the treatment of CDDP-induced hepatic and cardiac injuries.