Quantitative studies on the spatial distribution of geometric parameters of complex submarine sand waves in the developmental area are rare, and the correlation between the complex geometric parameters of sand waves and environmental variables has not been clarified. Based on measured data of water depth, sediment grain size and flow velocity in the western area of Hainan Island, the environmental variables of the study area were quantified and extracted. The morphological parameters of complex submarine sand waves were calculated using an automated extraction and analysis method, and the correlation between sand wave geometric parameters and environmental variables was analyzed. The results show that the morphological characteristics of submarine sand waves in the study area are complex and variable, with an average wavelength ranging from 64 to 340 m and an average wave height ranging from 0.39 to 4.13 m. There is a strong positive correlation between wave height and steepness, as well as between wave height and the average angle of the lee side. There is also a strong positive correlation between wavelength and symmetry, and a strong positive correlation between median sediment grain size and the average angle of the lee side and wave height. The development of submarine sand waves in the study area is less influenced by water depth. Under the action of tidal currents, sediment transport is mainly by traction, and the erosion of submarine sand waves is relatively weak. The evolution of sand waves is mainly characterized by vertical growth and migration, with wave height growth prioritized over wavelength increase. Under stable tidal flow conditions, regional sediment supply and sediment grain size can both affect the scale of submarine sand waves.