In this research paper, the interaction between Cu(II), Co(II), Cd(II) and Ni(II) with L2 and L4 have been studied by pH-metric technique at 0.1 M ionic strength in 70% ethanol-water mixture with the use of Irving-Rossotti and Calving-Bjerrum method. The data obtain were used to estimate the value of proton-ligand stability constant (pK) and metal ligand stability constant (logK). It showed that the metal ions form 1:1 and 1:2 complexes with L2 and L4.