Abstract: In this study, the effects of different mass concentrations (5, 10 and 15 mg/mL) of Sacha inchi leaf alcohol extract (SILAE) on Caenorhabditis elegans (C. elegans) longevity, mobility, reproductive capacity, resistance to oxidative stress and levels of ROS, lipofuscin and malondialdehyde (MDA) in vivo, as well as the effects of SILAE on enzymatic and non-enzymatic antioxidants in C. elegans were investigated by constructing a senescence model of C. elegans, with the aim of providing certain theoretical references to the further research and application of Sacha inchi leaf. The results showed that SILAE at 5 and 10 mg/mL significantly prolonged the life span of C. elegans compared with the blank group (P<0.05) by 59.3% and 30.2%, respectively, and 15 mg/mL SILAE also prolonged their life span but without significant differences. Meanwhile, their reproductive and motility abilities were also effectively improved by SILAE. In oxidative stress environments, SILAE prolonged the life span of C. elegans under H₂O₂ stress by approximately 2, 4, and 5-fold, respectively, and 5 and 10 mg/mL of SILAE also significantly prolonged the life span of C. elegans under juglone stress (P<0.05). The accumulation of ROS, lipofuscin (P<0.001), and MDA (P<0.05) in C. elegans was reduced to varying degrees by SILAE. In addition, both superoxide dismutase and catalase activities in C. elegans were highly significantly increased by SILAE (P<0.001), while glutathione peroxidase activity and glutathione content were significantly increased by SILAE at 5 mg/mL (P<0.05) and 10 mg/mL (P<0.01), respectively. In conclusion, SILAE has anti-aging property and is a new possible source of functional foods or alternative drugs with oxidative mitigation and aging retardation effects.