PROBLEM TO BE SOLVED: To provide an artificial seaweed bed which can grow seaweeds efficiently even in a region around an algal reef in a sea bed, and can artificially form a seaweed bed in a wide range of the sea bed, and to provide a forming method thereof.SOLUTION: An artificial seaweed bed is provided with an algal reef installed in a sea bed, and a reticulate member which covers the algal reef and a region around the algal reef in the sea bed. The reticulate member is characterized by being formed so that a mesh size in a sea bed side region located in the sea bed side may be smaller than a mesh size of a water surface side region located in a water surface side rather than the sea bed side region.【課題】水底における藻礁周辺の領域においても藻類を効率的に育成させることができ、水底の広い範囲に人工的に藻場を形成することができる人工藻場およびその形成方法を提供することを課題とする。【解決手段】水底に設置される藻礁と、該藻礁および水底における藻礁周辺の領域を覆う網状部材とを備え、該網状部材は、水底側に位置する水底側領域の網目寸法が該水底側領域よりも水面側に位置する水面側領域の網目寸法よりも小さくなるように形成されることを特徴とする。【選択図】図１
