A dye-containing polarizing film comprising a polarizing film material and a metal-containing dye represented by the following formula (I): ##STR1## wherein Me is a transition metal selected from copper, nickel, zinc and iron;Z is hydrogen, lower alkyl, lower alkoxy, sulfo or amino which is unsubstituted or substituted;Q is a 1-naphthol or 2-naphthol residue which is unsubstituted or substituted and has no or an additional phenylazo or naphthylazo group unsubstituted or substituted and in which a hydroxy group is adjacent to the azo group bonding to the benzene ring having Z and is linked with the transition metal denoted by Me to form the complex;when Q is the naphthol residue having no additional azo group, then T is naphthyl which is unsubstituted or substituted; andwhen Q is the naphthol residue having an additional azo group, the T is a phenyl or naphthyl group which is unsubstituted or substituted, which film exhibits comparable high polarizing activity with film using iodine and superior durability.