In this study twelve new lanthanide complexes are characterized. They were prepared from the reaction of the sodium salt of HL.HLO and HLS with different lanthanide ions. At first we intended to prepare the complexes having the formula [Ln(X)3(H2O)n] where X=L, LO and LS from the reaction of one mole of lanthanide ( III) ions with three moles of NaL Nal.O and NaLS but different formulas were obtained Conductivity measurements of the isolated complexes in chloroform showed significan advantage by showing that all complexes are neutral and non electrolyte. From elemental analysis, infrared. And UV Visible spectra, different structures are proposed. The spectroscopic studies showed that lanthanum (111) complexes have the formula [Ln(X)3.(HX)] while Neodymium complexes have the formula [Nd(X)3.(H2O)2] The remaining formula were of Gadolinium and dysprosium are [Gd(X)2(OH)(H2O)3]and [Dy(X)2.(OH)(H20)3]. The infrared spectra of the prepared complexes with the ligand HL showed that the carboxylatel group of the ligands is coordinated through one oxygen atom (unidentate). but in the complexes of (HLO) and (HLS), the ligands are coordinated through oxygen and sulfur atoms of P=O and P=S groups respectively, in addition to the oxygen atom of the carboxylate group.