Updated project metadata. The decline in oocyte quality is a limiting factor of female fertility; however, strategies to maintain the oocyte quality of aged women are not available. In this study, we showed that growth hormone (GH) supplementation in vivo not only alleviated the decline in oocyte number caused by aging, but also improved the quality and developmental potential of aged oocytes. Strikingly, GH supplementation reduced aneuploidy in aged oocytes. Proteomic analysis indicated that the ERK1/2 pathway was involved in the reduction in aneuploidy rate of aged oocytes, as confirmed both in vivo and in vitro. In addition, JAK2 might be involved in the regulation of ERK1/2 by GH in aged oocytes. Collectively, our findings revealed that GH supplementation protects oocytes from aging-related aneuploidy and enhances the quality of aged oocytes, and could be used to improve the outcome of assisted reproduction in aged women.