We explored the gas exchange, chlorophyll fluorescence properties and antioxidant enzymes in centipede grass (Eremochloa ophiuroides) infected with barley stripe mosaic virus (BSMV). The results showed that with progress of virus infection, the net photosynthetic rate (Pn) and stomatal conductance (Gs) in centipede grass was dramatically decreased, while the intercellular CO₂ concentration (Ci) was gradually increased. Further studies showed that the maximum quantum yield of PSII photochemistry (Fv/Fm), the efficiency of energy conversion of open PSII (Fv’ /Fm’), the actual efficiency of total PSII centers (F_PSII), and photochemical quenching (qP) were decreased, while the nonphotochemical quenching (NPQ) was increased after BSMV infection. Moreover, BSMV infection increased the antioxidant activities until 21 days of infection, and then was slightly decreased. The MDA contents were also increased after BSMV infection. There results suggested that the decreased Pn after BSMV infection was not resulted from the decrease of stomatal conductance, and the primary limitation of Pn was suppression of the number of open PSII reaction centers and the efficiency of light energy transformation by PSII reaction centers, thereby the electron transport were decreased. Additionally, the excessive excitation energy could not be dissipated efficiently, and reactive oxygen species (ROS) could not be removed efficiently, thereby resulting in membrane lipid peroxidation in centipede grass infected with BSMV.