A waterproof structure for an electronic device is provided that includes a speaker, a housing, and a cover. The housing holds the speaker and includes at least one through-hole to transmit sound produced by the speaker. The cover includes a first sheet and a second sheet laminated to the first sheet. The stiffness of the second sheet is greater than the stiffness of the first sheet, and the cover is fixed to the housing to seal the at least one through-hole.