Hemicorallium imperiale is a precious coral (family Coralliidae, order Alcyonacea) found in deep, cold waters of the western Pacific particularly around Japan, forming highly branched colonies with a characteristic red calcareous axis historically harvested for jewelry and decorative objects. The species is a slow-growing deep-sea organism with generation times potentially spanning decades, making it highly vulnerable to overharvesting and population collapse. Genomic data have been generated for this species and are available in public databases, enabling comparative studies of cnidarian evolution and ecology.