In the present study the corrosion of aluminum and  some of its alloys in 2M HCl was studied. The effect of some pyrimidine derivatives, as organic inhibitors, on the corrosion of aluminum and its alloys in HCl solution was studied. The techniques used of measurements were: (i) linear polarization (ii) galvanostatic polarization and (iii) electrochemical impedance spectroscopy. The corrosion rate of the investigated electrodes was found to be depended on the type and composition of the metal electrode.  The pyrimidine derivatives acted as mixed inhibitors in acidic media. It was found that the inhibition efficiency of the inhibitor greatly depended on the type, size, and concentration of the compound and on the electron density of the adsorption centers. The inhibitory effect of the investigated compounds resulted from their adsorption on the metallic surface via adsorption centers and /or electrostatic interaction between the organic compound and electrode. The adsorption of inhibitors on the metallic surface from 2.0 M HCl solutions obeyed the Temkin's adsorption isotherm. Results obtained from linear polarization, galvanstatic polarization and impedance measurements are in a  good agreement.