Latex agglutination of poly (allyl-a-D-glucopyranose/styrene) particle was investigated by utilizing the binding interaction between concanavalin A(Con A) and the sugar containing allyl-a-D-glucopyranose. The poly (allyl-a-D-glucopyranose/styrene) particle was synthesized by emulsion copolymerization of allyl-modified glucose and styrene monomers. The surface of colloid particle was assayed by dye-partition method using the phenol-acid reaction, which revealed that the number of glucose a particle was 1517. The Con A intends to absorb on the surface of the poly(allyl-a-D-glucopyranose/styrene) latex, when solid content of latex was higher than 0.02wt%. Absorption behavior of the Con A on the latex surface was closely related to the colloidal stability of the poly (allyl-a-D-glucopyranose/styrene) particle, which was determined by UV-intensities and ζ-potential analyses with varying Con A concentration.