A Kinetic study has been made on the pre-irradition grafting of aqueous acylic acid onto polypropylene nonwoven.,The effects of grafting condition, such as pre-irradiation dose, environment atmosphere, grafting temperature and monomer concentration were investigated.,The dependence of the grafting rate on pre-irradiation dose was found to be 0.445 order. It can be concluded that the grafting copolymerization proceeds via a radical mechanism. The apparent activation energy for the grafting polymerization was calculated to be 25.52 kcal/mol.,The products obtained from this experiment showed that hydrophilicity, gas penetrability and dying ability were improved. But mechanical strengh of products decreased with pre-irradiation dose over 2×10,6, rad compared with origonal sample.