The hydrological connectivity of tidal creek system is a key ecological process of coastal wetlands, and also an important way to maintain and repair coastal wetlands. Understanding how hydrological connectivity affects the diffusion potential of organisms between habitats is crucial for restoring and maintaining regional and local biodiversity. In this study, the field investigation and in-situ observation were conducted on three tidal gully with obviously hydrological connectivity gradient in the Yellow River Delta wetland in spring (May) and autumn (October) of 2021, respectively. We aimed to explore the spatial-temporal variation characteristics of macrobenthic community and their influencing factors under different hydrological connectivity gradients. The results showed that a total of 50 species of macrobenthos were collected, belonging to 4 phyla, 8 classes, 39 families and 45 genera, including 23 species of annelids, 23 species of Annelida, 18 species of Mollusca, 5 species of Arthropoda and 1 species of Nemertina. The community density, biomass and diversity index of macrobenthos were higher in spring than in autumn. In spring, Malacostraca, Polychaeta and Bivalvia with small size and strong adaptability were dominant, while in autumn, Crustacea and Gastropoda with strong activity were dominant. The species number, density, biomass and diversity of macrobenthic community tended to increase with the increase of hydrological connectivity, and the highest value appeared in the medium hydrological connectivity area. The study showed that the hydrological connectivity of the tidal creek system had significant effects on the habitat, community structure and diversity of macrobenthos, but the variation pattern of community structure and diversity with the gradient of hydrological connectivity existed the seasonal differences. This study will help to further understand the mechanism of hydrological connectivity of coastal wetlands on biological communities, and provide a scientific basis for wetland environmental protection and restoration.