This paper presents an in-depth analysis of the I (V) and I(V-T) characteristics of the Schottky Pt / ZnO nanowire diode. Detailed analyzes were performed to extract the various electrical parameters and information on the interface states. The characteristic parameters of the structure such as barrier height, ideality factor, saturation current and series resistance were determined from the current-voltage measurement. The ideality factor (3.58) value at room temperature is higher than unity probably due to the presence of the n-ZnO / p-Si heterojunction in series with the Pt / ZnO nanowire. The value of the computed barrier height of the diode (0.65 eV) using the thermionic emission model is in good agreement with the theoretically predicted value. Indeed, these two values obtained by the current-voltage I(V) characteristics suggested the presence of interface states between the Pt and the nanowire ZnO. To confirm this observation, we carried out the measurement C (V).