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Based on the observed data of precipitation, temperature and runoff over 1961-2012 and MODIS data source from 1990-2012, Variations of hydro-climatic variables (e.g.precipitation,temperature, runoff.) and NDVI (Normalized Differential Vegetation Index, NDVI) were analyzed and the coupling response relationships between runoff and precipitation, temperature and NDVI were investigated.Results indicate that during 1961-2012, hydro-climatic variables and NDVI both presented increasing trends in general.Runoff positively correlated to precipitation and NDVI while negatively correlated to temperature in annual scale, which illustrate increases in NDVI and precipitation would increase runoff while rise in temperature would lead to runoff reduction.However, annual mean NDVI positively correlated to both the precipitation and temperature which implies increases in temperature and precipitation would result in increase in NDVI.Being influenced by the Eastern Asia monsoon, precipitation, temperature, runoff and NDVI have presented a similar seasonal distribution pattern with higher values occurring in flood season (i.e.July and August, etc.) and lower values occurring in winter months (i.e.December etc.) although precipitation and temperature both have maximum in July while maximum NDVI occurs in August.Relationships between seasonal runoff and precipitation, temperature could be affected by changes in NDVI.Correlativity between runoff and precipitation in flood season is much stronger than that in dry season which means increase in NDVI may increase hydro-climatic correlativity to some extent.