The reaction of DyCl3.6H2O with the mixed ligand system consisting of o-vanillin based Schiff base ligand H2L [2-(2-hydroxy-3-methoxybenzylideneamino) phenol], dibenzoylmethane (Ph2acac) and acetylacetone (Acac) in the presence of triethylamine as the base afforded, di and tetranuclear dysprosium hydroxo clusters having formulae [Dy2(L)2(Ph2acac)2(H2O)2]3(1) and [Dy4(L)4(acac)2(OH)2(H2O)2(C6H5N)4] (2) respectively. The solid state structures of these products were established by Single Crystal X-ray diffraction technique. Magnetism studies reveal Dy4 exhibits slow magnetic relaxation behavior.