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We investigated the role of nitric oxide (NO) in the regulation of ascorbate-glutathione (AsA-GSH) cycle and water physiological characteristics of Arabidopsis thaliana by sodium hydrosulfide (NaHS). NaHS markedly increased the contents of H2S, NO, chlorophyll (Chl), and carotenoids, the activity of AsA-GSH cycle, ascorbate/dehydroascorbate ratio, net photosynthetic rate, Chl fluorescence parameters, transpiration rate, stomatal conductance, and relative water content in leaves and the biomass of wild-type Arabidopsis. However, NaHS markedly decreased malondialdehyde content and electrolytic leakage. Except H2S, above NaHS-induced promotions were suppressed by nitrate reductase (NR) inhibitor sodium azide (NaN3). Application of sodium nitroprusside (SNP) to (NaN3+NaHS)-treated wild type Arabidopsis (NaN3+SNP+NaHS) reversed above effects of NaN3+NaHS. However, NaN3+NaHS and NaN3+SNP+NaHS had no significant effects on H2S content. Meanwhile, we proved above results by using NO-associated NR gene mutant nia1,nia2. Above results suggested that NO participated in the regulation of AsA-GSH cycle and water physiological characteristics of Arabidopsis by NaHS.