Abstract: The red algae of Family Gracilariaceae are important and widely used economic species. However，their taxonomic status has caused great controversy in recent years due to the application of molecular biology technology. Aiming at this problem，the genera Gracilaria，Gracilariopsis and Polycavernosa as key disputed groups are focused, and their species diversity, research progress and problems are summarized with the affiliation that scholars tried to answer. Some supporting data from authors are introduced briefly as results as well. It is expected to provide relatively detailed and objective references for scientific and educational personnel who engage in the research of these groups.