Fe S N N N N S NH2 S Abstract A complex of Fe(III) with 4-amino-5-(pyridyl)-4H-1,2,4-triazole-3-thiol was prepared and evaluated as a photodegradation for polyvinyl chloride (PVC). Polyvinyl chloride was dissolved in THF solvent (5%, w/w) and functionalized with Fe (III) complex to form PVC films by means of solvent-casting method with a thickness of 40 μm. To study the effectiveness of Fe (III) complex additive, different concentrations (0.01, 0.02, 0.03, 0.04 and 0.05 g) were introduced into the PVC solution. The films’ photodegradation was investigated; the photodegradation activity of the compounds was determined by monitoring the carbonyl group, weight loss method and morphological study with irradiation time. The obtained experimental results showed that the additive behaved successfully as a photoinducer for the degradation process for the PVC films and the photooxidation rate increased with the increase of additive concentration.