Experiment uses the Suspension Polymerization, under the dual oxidation-reduction system of H2O2-xanthate and H2O2-FeSO4 initiating, the lipophilic- monomer of BMA is grafted on the frame of cotton fiber which prepares oil-absorbent fiber. It has studied the adsorption kinetics, adsorption transfer and isothermal absorption model of the oil-absorbent fiber for the oily wastewater under 25°C. The result shows that the adsorption kinetics of the oil-absorbent fiber for the oily wastewater accords with pseudo second order kinetic model, it could get that the initial swelling rate is increase with stirring speed increasing from fitting. Particles internal diffusion model analyzing shows that the diffusion rate of external diffusion and particles internal diffusion are similar, increasing the stirring speed could increase the internal diffusion rate and external diffusion rate. Increasing the stirring speed could increase capacity mass transfer rate and it benefits to absorb. The absorbing of oil-absorbent fiber for oily wastewater accords with Langmuir and Freundlich isothermal absorption model.