Abstract: Aquatic vascular plants have undergone an evolutionary transition from terrestrial to aquatic habitats, necessitating substantial adaptations to their surrounding environments. In particular, the different inorganic carbon environments between underwater and terrestrial habitats confer distinct ecological significance to the photosynthetic inorganic carbon utilization strategies of both plant types. This paper elucidates the particularity and diversity of inorganic carbon utilization strategies in aquatic plants and the significance of these studies. In addition, the potential advantages in studying plant adaptation mechanisms based on inorganic carbon utilization strategies in aquatic plants (especially Hydrocharitaceae) is analyzed. Overall, this paper aims to provide a novel perspective for studying the adaptative mechanisms and evolutionary processes of aquatic plants, as well as new directions for research in this field.