Abstract: Macromolecules, a pesticides-macromolecules combination, have been prepared. The pesticides bearing carboxyl or hydroxyl group are bonded to the carriers, such as cellulose and carboxymethyl cellulose (CMC), but it will set itself free from the main chain of the macromolecular carriers by hydrolysis. The substituted degree of pesticides on the corriers, cauld be adjusted by varying the controlling conditions.The high polymer so prepared will release pesticides free spontaneously but slowly by immersing in water, and the release rate will proceed slower and slower as the time flows.