Abstract: A soluble and conductive polyaniline(PANI) was synthesized in the presence of horseradish peroxidase(HRP) immobilized on the surface of the beads of alginic acid calcium and chitosan via glutaraldehyde crosslinking.Immobilization effects of loading rate,relative activity,and the enzyme's stability of the immobilized enzyme were measured.The results show that the beads immobilized HRP can be used to synthesize the water-soluble conducting polyaniline successfully.