An antimicrobial polymer coating composition comprising a polyhedral oligomeric silsesquioxane having a cage structure and having one or more reactive functional groups substituted on silicon atoms; a thermal initiator; and a photosensitizer, an antimicrobial polymer film comprising a cured product of the antimicrobial polymer coating composition, and an antimicrobial polymer film comprising: a substrate layer containing a polyhedral oligomeric silsesquioxane having a cage structure, in which one or more reactive functional groups are substituted; and a photosensitizes dispersed in the substrate layer, wherein the polymer film has oxygen permeability of 10 to 80 cc/m2 day.