【Aim】 To analyze and evaluate the interactive effects between complex environmental conditions and the distribution characteristics of mangrove forest, researchers explored habitat suitability of a mangrove forest and the spatial distribution pattern of suitable areas at a specific regional scale. 【Method】 A mangrove forest in Xiaohai, Wanning was chosen as the study site. The hydrodynamics, water quality and sediment, and terrain elevation were considered as environmental variables, and an evaluation structure model was developed through analytic hierarchy process (AHP). The value of each indicator was determined using the Delphi method, and the spatial distribution of suitable areas in Xiaohai were obtained based on GIS technology after normalized treatment of the environmental indicators. 【Result】 The results indicate that the main environmental variables affecting the growth and survival of mangroves in Xiaohai are water depth, tide level, tide range, and salinity. The area with high habitat suitability for mangrove forests is located approximately 121.6 hm² from the north entrance of the study area; the area with moderate suitability is located approximately 328.5 hm² from the southwest and southeast sides of the study area; and the area with low suitability is located approximately 137.2 hm² from the south and middle parts of the study area. 【Conclusion】 The climate, water quality, and hydrodynamic conditions are suitable for the survival and growth of mangroves in Xiaohai. The large number of cleared aquaculture ponds provided the basic ecological conditions for mangrove cultivation and restoration. However, habitat transformation, and a strategic selection of mangrove according to the principle of ecological niche are essential for successful restoration.