PROBLEM TO BE SOLVED: To obtain an antimicrobial composition having excellent hydrophilic nature and anticorrosion, and to obtain an antimicrobial composition-laminated metal substrate having the composition on the surface thereof. SOLUTION: This composition is an antimicrobial composition containing an antimicrobial resin, wherein the fungus resistance indication measured by the evaluation method in accordance with JIS Z 2911 6.2.2. is >=2 when the composition is made to be a film and the contact angle with water is <=25 deg., while the fungus resistance indication is >=2 and the contact angle with water is <=25 deg. after the film is immersed in water at 40 deg.C for 120 h.