Abstract:Achieving hydrological connectivity within wetlands is important for the integrity of wetland ecosystems in the Yellow River Delta. In this study, at the large scale, this study used Google Eearth Engine to quantify the hydrological connectivity in terms of wetland water area, overall hydrological connectivity index, and average monthly inundation frequency. The driving force analysis was conducted using gray correlation; at the typical regional scale of fresh and saline water interaction, three hydrological network connectivity indices were selected for the zonal hydrological connectivity. The results of the study found that: 1) Overall the area of the Yellow River Delta wetland water area rose and the overall connectivity index decreased trend, connectivity blockage occurred in the study area. Heavy inundation and permanent inundation were mainly concentrated in the shallow sea area. 2) Both the area of wetland water and overall connectivity index of Yellow River Delta showed seasonal trends. Driving factor of wetland water area change:annual average temperature> runoff> precipitation> sediment transport. (3)According to the hydrological connectivity evaluation criteria, the hydrological connectivity of the Yellow River Delta wetlands has been maintained at a medium level for 30 years from the regional scale. The overall hydrological connectivity of the Yellow River Delta wetland was declining, and the temperature changes had a great impact on the hydrological connectivity. The results of this study can provide a reference for the conservation and restoration of hydrological connectivity in the Yellow River Delta wetlands.