The purpose of the present invention is to provide a cephalopod breeding basket or a cephalopod escape preventing sheet, which can keep cephalopods in a viable state and be used for cultivating, domesticating, displaying, transporting, and storing cephalopods, and prevents cephalopods from escaping. Provided is a cephalopod breeding basket (10) that can keep cephalopods in a viable state and is configured such that a net-shaped sheet having a mesh number of at least 4 is used in at least a portion (a side surface section (1)) thereof. Also provided is a cephalopod escape preventing sheet that can keep cephalopods in a viable state and is configured such that a net-shaped sheet having a mesh number of at least 4 is used in at least a portion thereof.