PROBLEM TO BE SOLVED: To provide a sea cucumber fish reef equipped with a main body having a stable shape against falling. SOLUTION: The main body is made of a "+"-shaped cone-shaped concrete block and has a height smaller than the entire width of the "+"-shaped bottom surface, and the center width and the center width of the "+"-shaped bottom surface correspond to each other. It is a sea cucumber fish reef provided with 10, water passage holes 60, 70, 80 formed to intersect the main body vertically and horizontally, and water passage grooves 97, 98. [Selection diagram] Figure 1【課題】転倒に安定的な形状の本体を備えるナマコ魚礁を提供する。【解決手段】「＋」字錐体状のコンクリートブロックからなり、「＋」字状の底面全体幅より高さが小さいし、「＋」字状の底面中心幅と高さが互いに対応する本体１０と、本体に垂直と水平方向に交差するように形成された通水孔６０，７０，８０と、通水溝９７，９８とを備える、ナマコ魚礁である。【選択図】図１
