The relationship of the electric conductivity of single and multi component of colloidal catalyst FeCl3 Al(i Bu)3 Phen with their concentration was studied in hydrogenated gasoline solvent at 25℃ ,meanwhile,the UV Vis spectra of the corresponding component of the catalyst were detected.The experimental results showed that Al(i Bu)3 existed in associated state and dissociated into ion couple.The reaction between Al(i Bu)3 and FeCl3 was the main reaction to form colloidal core.The Fe(III) on the surface of the colloidal particles was reduced to lower valence by Al(i Bu)3.The stable complex formed by the reaction between Phen and Fe(II) could prevent Fe(II) from being reduced to lower valence.The colloidal particles were comparatively stable by means of the electric double layer yielded by a proper excess of Al(i Bu)3.The stable colloidal particles could be formed in the optimal ratio of the catalyst components.