The rosin modified acrylate latexes with the particle of core-shell structure for PVC floor adhesives was synthesized by seeded semicontinuous emulsion polymerization. The effect of amount of rosin, way to add rosin, proportion of core and shell monomers on the properties of latexes had been studied. When the amount of rosin was 2%, ratio of core /shell monomers was 1:2, its initial tack(#33) was1.3cm, cohesive strength was 0.32 MPa.