A platinum electrode modified with lanthanum hexacyanoferrate (LaHCF) was prepared by electrochemical scanning and characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and voltammetry. The results show that the deposit on the platinum substrate is composed of lanthanum potassium hexacyanoferrate (II) tetrahydrate. The electrochemical behavior of the LaHCF modified electrode was investigated preliminarily by voltammetry, and the experiments showed that hydrogen ion has a considerable effect on the electrochemical behavior of the modified electrode.