Potentiometric and UV spectroscopic measurements have been carried out to determine the stability constants for the complexation of the MoO(4)(2-) ion with D-(-)-quinic acid {(1R,3R,4S,SR)-(-)-1,3,4,5-tetrahydroxycyclohexane-1-carboxylic acid} in sodium chloride aqueous solutions for ionic strengths between (0.10 to 1.00) mol.L(-1) of sodium chloride at T = 298 K. The Job method of continuous variations was applied for the determination of the metal-to-ligand ratio which was 1:1 at pH = 6.50. Extended Debye-Huckel type (EDH), specific ion interaction theory (SIT), and parabolic equations were investigated to derive the necessary ionic strength dependence parameters, and the results were justified.