The new tridentate Schiff base ligand (HL)namely 2-{[1-(3-amino-phenyl)-ethylidene]-hydrazono methyl}- phenol containing (N N O)as donors atoms was prepared in two steps:Step (1): By the reaction of 3- aminoacetophenone with hydrazine monohydrate under reflux in methanol and drops of glacial acetic acid gave the intermediate compound 3-(1- hydrazono ethyl)-phenol amine.Step (2): By the reaction of 3-(1-hydrazono ethyl)-phenol amine with salicyaldehyde under reflux in methanol, gave the ligand (HL).The prepared ligand was characterized by I.R, U.V-Vis,1H- 13C NMR spectra and melting point and reacted with some metal ions under reflux in methanol with (1:1) ratio gave complexes of the general formula: [MClL]. Where: M= Mn(II), Fe(II), Co(II), Cu(II), Zn(II), Cd(II), Ni(II), and Hg(II).Products were found to be solid crystalline complexes, which have been characterized through the following techniques:Molar conductivity .Spectroscopic Method [FTIR and UV-Vis], additional measurement magnetic suspeliblity and Chloride content, The magnetic moment coupled with the electronic spectra suggested an tetrahedral geometry for all the complexes except[ NiClL] is Square-planar.The nature of the complexes formed were studied by Mole Ratio and the stability constant of the complexes have also been studied.