Abstract: The present invention is characterized by an underwater sightseeing craft, wherein a plurality of displacement bodies for sightseeing equipped with underwater sightseeing rooms are provided and paralleled with a fixed distance therebetween, wherein floating cavity bodies are provided outside each of said displacement bodies, wherein whole the said bodies are combined and integrated into one body by means of connecting members so as to be in a symmetrical form, wherein sightseeing windows are formed on each of said displacement bodies for sightseeing at a fixed depth below water, and wherein said floating cavity bodies are located so as not to obstruct a view through the sightseeing windows.