Abstract: In order to investigate the effects of exogenous hydrogen sulfide on rice seedlings growth and development, rice seedlings was treated with different concentrations of NaHS (0.1、0.2、0.4、0.8、1.6、3.2 mmol/L) , a donor of H2S, to find out the responses on physiological and biochemical of rice seedlings and the analysis of principal component analysis (PCA). The results showed that rice seedlings treated with low concentration (0.1 ~ 0.8 mmol/L) NaHS exhibited a significant increase in seedling growth (including plant height, root length and biomass), chlorophyll content, net photosynthetic rate (Pn) and chlorophyll photochemical rate (Fv/Fm). And decreased relative electric permeability of leaves. However, with the increasing of concentration of NaHS, the growth of seedling significantly was suppressed. PCA analysis indicated a distinct separation between control and treated profiles, especially, low concentration (0.1 ~ 0.8 mmol/L) NaHS and the control, and high concentration (1.6 ~ 3.2 mmol/L) NaHS and the control.