Abstract Cisplatin (CDDP) is an effective chemotherapeutic agent used to treat solid tumors, but it can cause irreversible hearing loss. Currently, there are no specific preventive measures available for this side effect. G protein-coupled receptor 55 (GPR55) exhibits antioxidant, anti-inflammatory, and anti-apoptotic properties and is implicated in various disease processes. Nevertheless, whether GPR55 plays a role in CDDP-induced hearing loss remains unclear.