A display medium includes: a first substrate having transparency and provided with a transparent electrode on one face thereof, a member having a plurality of penetration holes, the member being placed on a surface of the transparent electrode, the penetration holes penetrating the member from the transparent electrode surface side, the ratio of the length of each of the penetration holes to the largest hole diameter being two or more; a second substrate placed so as to face the transparent electrode side of the first substrate; an electrolytic solution containing a metal ion and placed so as to fill a space between the first and second substrates; and a counter electrode placed in a position so as to be insulated from the transparent electrode and in contact with the electrolytic solution.