Polymer plating of triazine dithiols on magnesium alloy AZ91 in 1 mol/dm(3)-NaOH aqueous solution was investigated. 6-Dihexylamino-1,3,5-triazine-2,4-dithiol monosodium salts (DHN) were selected based on the rate of film formation, film structure and corrosion resistance to magnesium alloys. The inhibition efficiency of magnesium alloys polymer-plated for only 10 min at 20degreesC in 8-mmol/dm(3)-DHN aqueous solution exceeded 96% after immersion for 3 h at 30degreesC in 1%-NaCl aqueous solution. The treated magnesium alloys have a corrosion rate of 0.011 mm/year.