Electrolytic deposit of indium, platinum and platinum-indium alloy on the surface of graphite electrodes has been studied using the scanning electron microscopy and the stripping voltammetry. The scanning electron microscopy method has revealed that platinum-indium alloy on the surface of the graphite electrode contains indium, platinum and chlorine. But platinum is unable to be determined on the surface of the graphite electrode without a metal activator due to its precipitation in very small quantities. Under the anodic oxidation of indium-platinum precipitation, the anodic peaks caused by the selective electro-oxidation of indium from the intermetallic compounds with platinum are observed on the current-voltage curves. Wherein, platinum remains on the electrode surface, and can be oxidized from the electrode at the potentials of the electrode purification (more than 1 V).