Abstract: Site selection of marine ranching plays a key role in marine ranching construction. Appropriate site is the precondition of a successful marine ranching construction. In this study, we selected 34 indicators as the factors for marine ranching suitability evaluation (Coastline stability, marine functional zoning, marine ecological red lines, aquaculture water tidal flat planning, marine engineering and facilities), and established an index system for marine ranching site selection. On this basis, according to the actual situation of Wailingding Island of Zhuhai, we selected eight indexes including length and area change intensity of island coastline, marine functional zoning, marine ecological red line, beach planning of aquaculture waters, ports, anchorages, navigable areas and submarine pipelines, to evaluate the suitability of marine ranching site selection in that sea area by using the spatial analysis method of GIS. The results show that there was no most suitable and more suitable area for marine ranching construction, and the areas of generally suitable and unsuitable areas for marine pasture construction were 33.09 and 45.59 km², respectively. The suitable area for marine ranching construction was similar to the existing artificial reefs and planned marine ranching areas in Zhuhai.