A code display medium includes a code image display portion which arranges a plurality of code images side by side in a circumferential direction around an axis of screw fastening and which displays the plurality of code images so as to be optically readable, each of the plurality of code images including identification information for identifying at least one of a fastening material for the screw fastening and/or an object to be fastened by the screw fastening and a fixing portion which fixes the code image display portion to a position that is on the object to be fastened and that can be simultaneously captured with the fastening material in a state where the screw fastening is performed.