Seagrass beds are widely distributed in the coast of Aomori prefecture. Seagrass beds serves as fishing ground of the sea cucumber in Mutsu-bay. The artificial shelter was developed for growing both sea cucumber and seagrass with together. Experiment using the artificial shelter was done in the coast of the Mutsu Bay during several months, and the growth of seagrass Zostera caespitosa and japanese common sea cucumber Apostichopus japonicus were observed around artificial shelter. Natural and transplanted seagrass were collected and increasing in growth rates of each organism was confirmed when they were together in the shelter. These results showed the artificial shelter was effective for the increase of seagrass and sea cucumber resources.