Deep-sea hydrothermal vents are usually considered as extreme environments with high pressure, high temperature, scarce food, and chemical toxicity, while many local inhabitants have evolved special adaptive mechanisms for residence in this representative ecosystem. In this study, we constructed a high-quality genome assembly for a novel deep-sea anemone species (Actinostola sp.) that was resident at a depth of 2,971 m in an Edmond vent along the central Indian Ocean ridge, with a total size of 424.3 Mb and a scaffold N50 of 383 kb. The assembled genome contained 265 Mb of repetitive sequences and 20,812 protein-coding genes. Taken together, our reference genome provides a valuable genetic resource for exploring the evolution and adaptive clues of this deep-sea anemone.