In this study, chitosan-coated alginate microspheres were prepared by the ionic complexation of alginate and chitosan biopolymers to use in embolization and/or chemoembolization studies. Biopolymeric microspheres were prepared by the ionic gelation technique of alginate with a suitable divalent cation (i.e. CaCl2) in a suspension medium composed of mineral oil and petroleum ether including emulsifier (i.e. Tween-80) and then obtained microspheres were coated with chitosan in an aqueous chitosan solution while the medium was magnetically stirred. The obtained microspheres are in the size range of 100-400 mu m and they can be prepared as required by changing the preparation conditions (i.e. stirring rate, concentration of biopolymers, molecular weight and concentration of chitosan, etc.). In the in vivo studies, New Zealand rabbits were used as the test animals. Both complete and partial embolization of the kidney were achieved by using the microspheres. The renal angiograms obtained before/after embolization and the histopathological observations showed the feasibility of the chitosan-coated alginate microspheres as an alternative embolization and/or chemoembolization agent.