This study investigated the effects of Ganoderma lucidum (FYGL) on streptozotocin (STZ)-induced apoptosis in INS-1 cells. Various assays were performed, including cell viability, apoptosis, ELISA, and western blot assays. The results showed that FYGL improved beta cell viability and protected against STZ-induced apoptosis in a dose-dependent manner. FYGL also improved insulin secretion by decreasing JNK activation and increasing PDX-1 levels. The discussion matches previous studies showing that oxidative stress induces beta cell damage and STZ causes beta cell apoptosis and dysfunction. The conclusions are that FYGL protects pancreatic beta cells against damage, improves insulin secretion, and could be a promising agent for