Objective To explore the effect and possible mechanism of petroleum ether extract from Gastrodia elata on A amyloid β-protein deposition in Caenorhabditis elegans(C.elegans).Methods C.elegans was used as the model organism,and the experiment was divided into blank group(Control group),GEPEE 0.5 mg·mL-1 group and GEPEE 1 mg·mL-1 group.The effects of GEPEE on paralysis,life span,oxidative stress,heat stress,reactive oxygen species(ROS)level and Aβ aggregation of C.elegans were investigated,qRT-PCR was used to detect the changes of gene expression related to insulin/IGF-1 signaling pathway(IIS)in C.elegans.The main components were analyzed by high performance liquid chromatography(HPLC).Results Compared with Control group,GEPEE could significantly improve the paralysis phenotype of C.elegans(P<0.01),prolong the lifespan of C.elegans(P<0.01),enhance the motility of C.elegans(P<0.01),and increased the resistance to external oxidative stress(P<0.01),the stress ability of high temperature(P<0.01),improved the deposition of Aβ in vivo(P<0.01),decreased the ROS content in C.elegans(P<0.01),decreased the expression levels of Aβ and DAF-2(P<0.01),increased the expression levels of DAF-16 and its target genes SOD-3,GSH-Px,HSF-1 and its target gene HSP-16.2,SKN-1 and its target gene GST-4(P<0.01).Its main components were p-hydroxybenzyl alcohol and p-ethoxylbenzyl alcohol by HPLC.This study showed that GEPEE can reduce Aβ-induced toxicity in CL4176 C.elegans by reducing ROS level in vivo,increasing antioxidant level and regulating IIS pathway.Conclusion GEPEE can inhibit the toxicity of Aβ protein,and its mechanism is related to the regulation of IIS signaling pathway.