Plantago psyllium mucilage (PSY), an anionic natural polysaccharide consisting of pentosan and uronic acid obtained from the seeds of Plantago psyllium (Plantago family), was grafted with acrylonitrile (AN). Graft copolymers were prepared by ceric ion initiated solution polymerization technique and were characterized by FT-IR spectroscopy, scanning electron microscopy and differential scanning calorimetry. These copolymers are good flocculating agents for removal of suspended (SS) and total dissolved solid (TDS) in sewage wastewater treatment. The effects of copolymer dose, pH and contact time on flocculation capacity of one selected copolymer sample were studied by jar test method. The suitable pH range for maximum solid removal was 7.0 to 9.2 and the optimum copolymer dose was 1.2 mg/L. The overall process for solid removal took 4 h. X-ray diffraction (XRD) patterns of grafted copolymer, PSY grafted polyacrylonitrile (PSY-g-PAN)and solid waste, before and after treatment are used to suggest the interaction of the solid waste with PSY-g-PAN copolymer.