Anion adsorption behavior on Au colloid surface was investigated in virture of depositing monolayers of Au colloid on the self-assembled monolayers of cysteamine on a gold electrode. Po- tential-dependent anion adsorption-desorption waves via the nonfaradaic current were obtained by means of cyclic voltammetry at Au coltoid-modified gold electrodes in the potential range of -2 00-600 mV. The adsorption sequence in the order of adsorption peak potentials (Epa) is OH- >citrate3 ->H2PO4- >Cl->SO42->ClO4->NO3-. Among them, citrate3- exhibited an en- tirely irreversible adsorption. A rise in temperature can increase the rates of adsorption-desorp- tion and improve the reversibility of the adsorption-desorption of Cl-, SO42-, ClO4-, NO3- and H2PO-4. The adsorption peak potentials shifted more negatively for Ca. 63 mV as the anion con- centrations were increased by a decade factor. The change of pH from 7 to 1 slightly affected the adsorption peak potentials of Cl- and NO3-. Au colloids with a smaller size (16 nm) gave rise to a better reversibility of the adsorption-desorption process and lower adsorption currents. The ex- perimental results of citrate ions adsorption on Au colloid surface show that Au colloids with a smaller size prepared by sodium citrate method exhibited a higher stability in the solution in com- parison to those with larger sizes because of its higher ratio of charge/mass. In other words, the smaller gold nanoparticles are covered with citrate ions monolayer that can also be formed at larg- er gold nanoparticles by means of electrochemical scan. Anion adsorption behavior on Au colloid surface was investigated in virture of depositing monolayers of Au colloid on the self-assembled monolayers of cysteamine on a gold electrode. Po-tential-dependent anion adsorption-desorption waves via the non-faradaic current were obtained by means of cyclic voltammetry at Au coltoid-modified gold electrodes in the potential range of -200-600 mV. The adsorption sequence in the order of adsorption peak potentials (Epa) is OH-> citrate3-> H2PO4-> Cl-> SO42-> ClO4 A rise in temperature can increase the rates of adsorption-desorpation and improve the reversibility of the adsorption-desorption of Cl-, SO42-, ClO4- The change in pH from 7 to 1 slightly affected the adsorption peak potentials of Cl-, NO3- and H2PO- 4. The adsorption peak potentials shifted more negatively for Ca. 63 mV as the anion con- centrations were increased by a decade factor. and NO3-. Au colloids with a smaller size (16 nm) gave rise to a better reversibility of the adsorption-desorption process and lower adsorption currents. The ex-perimental results of citrate ions adsorption on Au colloid surface show that Au colloids with a smaller size prepared by sodium citrate method featured a higher stability in the solution in com- parison to those with larger sizes because of its higher ratio of charge / mass. In other words, the smaller gold nanoparticles are covered with citrate ions monolayer that can also be formed at larg er gold nanoparticles by means of electrochemical scan.