Abstract: As an important research area for tropical marine biodiversity in China, Hainan Province hosts rich mollusca resources. In the report, the research progresses on the diversity characteristics of the mollusks of Hainan Province, the classical and systematic taxonomy, and the major limitations were reviewed. The documented mollusks cover 5 classes, 185 families, and 1128 species. However, the current research are limited by the morphological misidentification, the scope limitation of the survey, the habitat fragmentation, and the technical constraint in molecular marker applications for phylogenetic resolution. In the future, based on the environmental DNA metabarcoding for biodiversity monitoring, the multidimensional data fusion, and the phylogenomics technology, the high-resolution phylogenetic frameworks can be constructed, the cross-regional collaborations can be strengthen, and the investigation and protection of the mollusca resource can be improved.