In this study, PAM chains were grafted onto the backbone of cellulose extracted from pandan leaves (pandanus amaryllifolius roxb.) via microwave assisted method. The performance of grafting between extracted cellulose and PAM was verified through the percentage of grafting (% G). The grafting of the PAM chains on the polysaccharide backbone was confirmed by SEM morphology analysis and FTIR spectroscopy. The efficiency of grafted copolymers was tested on removal of COD of synthetic dye, reactive black 5, conducted using a jar test experiment. The results obtained showed that the best achievement of the synthesized PAM-g-cellulose was in initial dye concentration of 0.025 g/l, with flocculant dosage of 0.06 g at pH 11.