Aging is a complex process in which the structure and function of various tissues and organs gradually decline with age, and ovarian aging affects the reproductive capacity of females and induces age-related diseases. Resveratrol, a natural polyphenol compound, extends the lifespan and has a protective effect on ovaries of vertebrates. However, the effects and underlying mechanisms of resveratrol delaying ovarian aging are unclear. In the present study, using an annual fish N. guentheri, we demonstrated that senescence-associated-beta-galactosidase (SA-β-gal) activity and lipofuscin accumulation increased with age in the ovaries, and resveratrol reversed this phenomenon. Resveratrol increased proliferating cell nuclear antigen (PCNA) expression and the oocyte proportions of primary growth stage, cortical alveolus stage and vitellogenesis stage, and decreased the number of atretic follicles in the ovaries of 6-, 9-, 12-month-old fish. Moreover, the expression of SIRT1 and NRF2 decreased and the levels of NF-κB, pro-inflammatory cytokines IL-1β, TNF-α and IL-8 and endoplasmic reticulum (ER) stress markers GRP78 and CHOP increased with aging, while resveratrol up-regulated SIRT1 and NRF2 expression and down-regulated NF-κB, IL-1β, TNF-α, IL-8, GRP78 and CHOP levels in the ovaries of 6-, 9-month-old fish. In HEK293T cells, knockdown SIRT1 decreased NRF2 and increased NF-κB p65, pro-inflammatory cytokines (IL-1β and TNF-α) and ER stress marker GRP78 expression markedly. Silencing SIRT1 and then treating the cells with resveratrol significantly reversed the phenomenon. Collectively, resveratrol might activate SIRT1/NRF2 to reduce inflammation and ER stress, and finally delay ovarian aging in a short-lived fish. This study highlights the protective effect and mechanism of resveratrol on ovarian aging.