A kinetic study was made on the preirradiation grafting of styrene onto cotton cellulose. The dependencies of the grafting yield on preirradiation (in air) dose, grafting reaction time and grafting temperature were investigated respectively. The grafting yields as a function of above reaction conditions weree xpressed by derived using approximate formulae. The results about the relation between the grating yields with these grafting conditions calculated by the equations derived in this work were consistent with respective experimental data. It means that the experimental results are correct and the derived equations are reasonable.