AIM: To explore the mechanism of osthole on elderly spontaneously hypertensive rats. METHODS: 20-month-old spontaneously hypertensive rats (SHRs) and healthy Wistar-Kyoto (WKY) rats were purchased. SHRs were treated with osthole (i.g.) for 8 weeks. The systolic blood pressure and diastolic blood pressure of rats were monitored. Hematoxylin-eosin staining (H&E), periodic acid-schiff staining (PAS) and Masson staining were used to observe the pathological changes of rat kidney tissues. The activity of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) in rat kidney was detected by ELISA kit. PI3K/Akt/mTOR signaling pathway related proteins were detected by western blot. RESULTS: Osthole reduced the systolic and diastolic blood pressure of SHRs, improved the histopathological changes of SHRs kidney, reduced the activity of MDA in SHRs kidney, and increased the activity of SOD and GSH. Osthole reduced the levels of p-PI3K, p-Akt and p-mTOR. CONCLUSION: Osthole reduces the activity of PI3K/Akt/mTOR signaling pathway and exerts a protective effect on renal oxidative stress injury in aged spontaneously hypertensive rats.