The effect of hydrostatic pressure on the interface state density and Schottky barrier diode parameters such as ideality factor and barrier height obtained from the current-voltage (I-V) characteristics of Au/n-InP Schottky diodes was studied. It is shown that the ideality factor and the barrier height values of Au/n-InP diodes are in the range 2.36-1.93 and 0.546-0.579 eV for the 0.0-5.0 kbar pressure interval at room temperature, respectively. We have seen that the barrier height for Au/n-InP Schottky diodes has a linear pressure coefficient of 6.87 meV/kbar (=68.7 meV/GPa), approximately equal to that found for the band gap of InP. This means that the Fermi level is a reference level which is pinned to the conduction band minimum as a function of pressure. On the other hand, the interface state density decreases with increasing hydrostatic pressure due to the rectifying properties of the diode. (C) 2010 Elsevier Ltd. All rights reserved.