PROBLEM TO BE SOLVED: To provide a seaweed bed reef stuffed with stones and using a net bag, easily producible, installable by a small number of people with a fishing boat including a small boat or a work ship, allowing artificial management such as substrate renewal and cleaning by collection or re-installation, and fixed amount investigation by pulling up, and making tangle easy to adhere/grow on a thick net material Laminariales and other seaweed adhere/grow.SOLUTION: This seaweed bed reef stuffed with stones and using a net bag includes a net bag 2, a stone material 3 stuffed in the net bag 2, and a rope 4 tightening the outer periphery of the net bag 2 stuffed with the stone material 3 or pulling the net bag 2 to strain, has a quality of transforming with the ruggedness of the sea bottom and adjusting thereto, and allows to easily perform substrate renewal of an epiphytic surface by turning over. Furthermore, the reef includes a net body 5 which is stretched on the upper surface, upper and lower surfaces, upper and lower surfaces and side surface, side peripheral surface, other prescribed surface, or entire circumferential surface of the net bag 2, and is formed in a thickness or a mesh shape different from that of the net bag 2, corresponding to the kind of objective seaweed.【課題】簡易に製作でき、小型船を含む漁船或いは作業船により少人数で設置できると共に、回収や再設置で基質更新や除掃など人為的な管理が可能であり、引揚げて定量調査が可能であり、且つ、太い網地に着生・生育しやすいコンブ類や他の海藻を着生・生育させることができる、網袋を用いた石詰め藻場礁を提供する。【解決手段】網袋２と、網袋２内に詰めた石材３と、石材３を詰めた網袋２の外周を締め付け、又は、網袋２を引張して緊張させるロープ４を備え、海底の凹凸に追従し変形して馴染む性質を有し、且つ、反転により着生面の基質更新が容易に行なえる、網袋を用いた石詰め藻場礁であって、更に、網袋２の上面、上下面、上下面及び側面、側周面、その他の所定面、又は、全周面に張設され、目的海藻の種別に対応させて網袋２の網地と異なる網地の太さ又は目相に形成された網体５を備える。【選択図】図１
