This study investigated the effect of H2S on chloroplast antioxidant capacity and chlorophyll fluorescence of wheat seedlings under copper stress. The results showed that copper stress significantly increased the activities of ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), glutathione peroxidase (GPX), and the contents of MDA and H2O2 in chloroplast and non-photochemical quenching (qN), compared with control. However, copper stress significantly reduced the values of maximum photochemical efficiency of PSII (Fv/Fm), photochemical quenching (qP), quantum efficiency of photochemistry (ΦPSII), and the net photosynthetic rate (Pn), compared with control. Meanwhile, copper stress significantly reduced the fresh and dry weight per plant. Compared with copper stress alone, pretreatment with different concentrations of NaHS plus copper stress enhanced the activities of the above enzymes in chloroplast; and the values of Fv/Fm, qP, qN, ΦPSII, and Pn, especially for copper plus 0.8 mM NaHS. Compared with copper stress alone, pretreatments with different concentrations of NaHS plus copper stress also reduced the contents of MDA and H2O2 in chloroplast and increased the fresh and dry weight per plant, especially for copper plus 0.8 mM NaHS. Our results suggested that H2S has important role for acquisition of copper tolerance by enhancing chloroplast antioxidant capacity and the function of photosynthetic apparatus of wheat.