Abstract: The dubbed "living dinosaur" Halophila beccarii Asch., among one of the oldest lineage of seagrasses, is a typical intertidal seagrass in Indo-Pacific area.It is biologically characterized by being ancient, tiny, fast-growing, monoecious, protogynous, low genetic variation and having both annual and perennial life cycles forms.Ecologically, it is considered as a colonizing or a pioneer seagrass species and a "tiny but mighty" seagrass species, since it may recover quickly from disturbance generally.H.beccarii and its' significance are neglected to a large extent due to its limited distribution, very tiny plant size, fast turn over, easily buried-shoot by sediment in the field.The intensive human disturbances in the intertidal zones pose profound threats to this species.The global population trends indicate the species is declining and it was listed as "Vulnerable" by the International Union for Conservation of Nature (IUCN) under criterion B2 and among one of the ten seagrass species which are at elevated risk of extinction in the world.Based on the biological and ecological features and the threatened situation of H.beccarii, we propose that:(1)include it into "China red data book of endangered species"; (2)take measures to conserve the soil seed bank; (3)the seagrass plants should be appended to the key protection objects list of the associated mangrove reserves; (4)ex-situ conservations may be carried out when facing inevitable loss of seagrass habitats; (5)some studies, such as releasing of seed dormancy, promoting of seed germination, cultivating in the laboratory and transplanting in the field, are encouraged to enhance.