Graft copolymerization of binary mixture of methyl methacrylate (MMA) and acrylonitrile (AN) has been carried out onto Agave americana fibers in the presence of Ce (IV) ions at 45.0 ± 0.1 0C. The addition of acrylonitrile as a comonomer has shown a significant increase in graft copolymerization of methyl methacrylate onto the lignocellulosic fibers. A synergistic effect of acrylonitrile on methyl methacrylate has been observed when graft copolymers were prepared using different feed compositions (fMMA) ranging from 0.2 to 0.8 at constant feed molarity of 5.0 x 10 -1 mol dm-3. The rate of grafting has shown a linear dependence on the concentration of comonomers within the range of feed molarity from 3.5 x 10-1 to 5.0 x 10-1 mol dm-3. The variation of grafting parameters such as graft yield and graft efficiency has been studied as a function of feed molarity and feed composition. The graft copolymers were characterized by various techniques such as FT-IR, TGA/DTA, X-RD, and SEM. Further graft copolymers were evaluated for the physico- chemical properties such as swelling behavior in different solvents, moisture absorption behavior, and resistance to chemicals as a function of percent grafting. The mechanism for grafting has been proposed based upon experimental observations.