The effects of different shading treatments (25%,50%,75% and 100% of full sunlight) on the growth,photosynthetic characteristics and chlorophyll fluorescence parameters of Rosa hybrida were examined in order to know the growth and physiological responses of R.hybrida to light regimes.(1)It has been found that with the decreasing light intensity,the leaf thickness,and flower diameter and flower formation rate decreased,while the Chl content increased.The net photosynthetic rate (P_n),transpiration rate (T_r),stomatal conductance (G_s) and intercellular CO₂ concentration (C_i) all decreased with the decreasing of light intensity,while the stomatal limitation value (L_s) increased.(2)The light compensation point (LCP),light saturation point (LSP) and dark respiration rate (R_d) also decreased as a mechanism of physiological adaptability to light decreasing.The adaptability of R.hybrida to light was wide because the LSP was 600～1 200 μmol·m^-2·s^-1 and the LCP was 29.89～62.95 μmol·m^-2·s^-1.The CO₂ compensation point (CCP) was 78.16～89.41 μmol·mol^-1,the CO₂ saturation point (CSP) was about 1 100 μmol·mol^-1 and the potential maximum photosynthetic capacity (P_m) was 13.06～25.63 μmol·m^-2·s^-1,which indicated that light intensity and CO₂ concentration have greater impact on photosynthesis rate.(3)The chlorophyll fluorescence parameters indicated that with the increasing of light stress,the reaction center of PSⅡ was destroyed,photosynthetic electron transform capability was weakened and photosynthesis was restrained.It is indicated that R.hybrida is a sun plant with shade tolerance.Moderate shading (75% of full sunlight) can improve its photosynthetic capacity and the flower quality,and reduce the photoinhibition in R.hybrida.