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The current study compares responses to open field and shade enclosure condition (plastic shading nets were used to imitate a natural shading rate) to test the possible benefit of shading in terms of physiological and growth characteristics in Ginkgo biloba L. during the reproductive stage in summer. Compared with the net shade treated plants (NS-plants), the open-field plants (Oplants) contained lower chlorophyll (Chl) a ? b content and Chl a/b ratio, and exhibited a decreased ratio of Chl/ Car. Results showed that the chlorophyll fluorescence characteristics including maximum PSII photochemical efficiency (F v /F m ), potential electron transport per excited leaf cross-section (ET 0 /CS 0 ), potential electron transport per PSII reaction center (ET 0 /RC), dissipation per excited leaf cross-section (DI 0 /CS 0 ), dissipation per PSII reaction center (DI 0 /RC), and overall performance index of PSII photochemistry on absorbtion basis (PI ABS ) were altered by the net shade treatment. It was observed that the grana were illegible and difficult to distinguish by transmission electron microscopy, especially, in the cells of O-plants in which phenols were observed in the vacuole. The phenomenon of photoinhibition induced by excessive irradiance was confirmed by the abnormally high levels of the reactive oxygen species. Moreover, antioxidant enzymes activities were induced by high irradiance in the ginkgo leaves. In addition, significant differences were observed in the fresh weight and dry weight of leaves and seeds. Comparison of the variation of underlying physiological and biochemical mechanisms suggested that there was a better efficiency of ginkgo plants under artificial net shade conditions. Therefore, ginkgo plant would be best grown at 30-35 % of natural irradiance in summer months to be more profitably harvested and then meet the increasing demand of leaves and seeds.