A metal/resin composite structure comprising: a metal member having a fine uneven surface; and a polyamide-based resin member bonded to the metal member, wherein (i) the fine uneven surface of the metal member includes a fine uneven surface on which the large number of protrusions having an interval period of equal to or greater than 5 nm and equal to or smaller than 500 um are erected; (ii) the polyamide-based resin member includes a metal soap, where a content of montanic acid metal salt occupying the metal soap is equal to or more than 20% by mass and equal to or less than 100% by mass; and (iii) the polyamide-based resin member satisfies the following condition and condition: a glass transition temperature (Tg) observed by a differential scanning calorimeter is equal to or higher than 85°C and equal to or lower than 140°C; and a crystallization temperature (Tc) observed by a differential scanning calorimeter is equal to or higher than 250°C and equal to or lower than 292°C, and wherein the interval period, glass transition temperature and crystallization temperature are determined according to the description. a metal member having a fine uneven surface; and a polyamide-based resin member bonded to the metal member, wherein (i) the fine uneven surface of the metal member includes a fine uneven surface on which the large number of protrusions having an interval period of equal to or greater than 5 nm and equal to or smaller than 500 um are erected; (ii) the polyamide-based resin member includes a metal soap, where a content of montanic acid metal salt occupying the metal soap is equal to or more than 20% by mass and equal to or less than 100% by mass; and (iii) the polyamide-based resin member satisfies the following condition and condition: a glass transition temperature (Tg) observed by a differential scanning calorimeter is equal to or higher than 85°C and equal to or lower than 140°C; and a crystallization temperature (Tc) observed by a differential scanning calorimeter is equal to or higher than 250°C and equal to or lower than 292°C, (i) the fine uneven surface of the metal member includes a fine uneven surface on which the large number of protrusions having an interval period of equal to or greater than 5 nm and equal to or smaller than 500 um are erected; (ii) the polyamide-based resin member includes a metal soap, where a content of montanic acid metal salt occupying the metal soap is equal to or more than 20% by mass and equal to or less than 100% by mass; and (iii) the polyamide-based resin member satisfies the following condition and condition: a glass transition temperature (Tg) observed by a differential scanning calorimeter is equal to or higher than 85°C and equal to or lower than 140°C; and a crystallization temperature (Tc) observed by a differential scanning calorimeter is equal to or higher than 250°C and equal to or lower than 292°C, a glass transition temperature (Tg) observed by a differential scanning calorimeter is equal to or higher than 85°C and equal to or lower than 140°C; and a crystallization temperature (Tc) observed by a differential scanning calorimeter is equal to or higher than 250°C and equal to or lower than 292°C, and wherein the interval period, glass transition temperature and crystallization temperature are determined according to the description.