The present invention relates to artificial shells and a pipe used for the artificial shells to maintain the interval between the shells. More specifically, the present invention relates to artificial shells and a pipe to maintain the interval between the shells, in which, in order to cultivate adherent aquatic products, such as oysters and sea squirt, the structure of the artificial shells mounted on a hanging line is improved, and thus simplified and easily manufactured. The structure of the artificial shell is robust and the artificial shell can be conveniently installed, so that a cultivation work can be rapidly and easily performed. When a work of attaching a larval stem is performed, the larval stem can be prevented from being separated from the artificial shell due to external force such as hydraulic pressure. In addition, the pipe to maintain the interval between the artificial shells is additionally manufactured. Accordingly, the work of installing the artificial shells can be efficiently performed. According to the present invention, the artificial shell includes: an artificial shell body having the shape of a plate formed in the center thereof with a plurality of insertion holes, into which the hanging line is inserted, and having a predetermined thickness anti-flexural ribs formed on both or one of top and bottom surfaces of the artificial shell body to surround an outside of the artificial shell body with a predetermined height to prevent flexure a larval stem fixing groove formed in a larval stem fitting groove to prevent the larval stem from being separated from the shell and a larval stem protecting groove to prevent the larval stem from being cut. In addition, the pipe to maintain the interval between the artificial shells includes: a tubular body formed through the center thereof and having a predetermined height and a plurality of shell support ribs formed at an outer circumferential surface of the body in a longitudinal direction while being spac
