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In this study, oxide coatings were produced on pure zirconium by micro arc oxidation method in the electrolytes containing sodium silicate and dierent amounts of yttrium acetate tetrahydrate (14 g/l) for the same coating duration of 1 h. The surface roughness, microstructure, phase content and chemical composition of the coatings were characterized by using scanning electron microscopy, prolometry and X-Ray diractometry. It was found that the surfaces of coatings on zirconium consist of monoclinic-ZrO2, tetragonal-ZrO2 phases. The coating thickness decreases with addition of yttrium acetate tetrahydrate while it does not change signicantly with the increase of its amount. The clustered equiaxed features were formed on the surfaces of the coatings. As the amount of yttrium acetate tetrahydrate in the electrolyte solution increased, the coating/substrate interface smoothened. Two main regions of the coating, the outer dense region (I) and the porous inner region (II), became signicant with addition of YAT into the electrolyte.