||In the last few decades, many different reactions, elimination, dehydrochlorination, grafting polymerization via cationic and free radical pathways and substitution, on PVC have been reported. Recently, PVC has been treated with ethylene diamine (EDA) for high efficient degree of substitution. Although substitution reaction of PVC with EDA has been widely used for further reaction, as far as we know, the optimum conditions for substitution has not been reported. In this study, PVC was treated with 80% and 99% EDA (PVC-EDA hereafter) at different temperature (RT, 50, 70, 90 ℃). FT-IR was used to confirm the chemical structure. Morphology was observed through SEM and atomic contents were analyzed from EDS and XPS for ensuring the degree of substitution.