The conducting platinum cluster compound K1.64Pt(C2O4)2 was electrochemically synthesized on a glassy carbon electrode through electrooxidation of K2Pt(C2O4)2 in an aqueous medium using a single potential step and cyclic voltammetry methods. Two kinds of mechanism, namely one-step and two-step processes, were proposed to account for the electrocrystallization of K1.64Pt(C2O4)2. The excellent conductivity of the fibrous material formed on top of the working electrode was demonstrated by its rare voltammetric properties and suggests its potential application as an ultramicro electrode. The diffusion steady state obtained during the cyclic voltammetry reflects the stability of the conducting material over the potential range investigated. In addition, the conducting fibers prove to be effective to the electroactive species in solution for the plateau-current appeared at the same potential as the peak-shaped current. Detailed studies are required to investigate kinetics of electrocrystallization, which will be helpful to control the formation of the conducting material on the electrode.