Wu and Tong proposed the calculation method of Patterson function obtained directly from the LEED I-V curves which shows the relative position of surface atoms as an image. We have made the calculation program of Patterson function and applied to the structural analysis of the Si(1 1 1) 1 x 1-Fe surface. Surface structure was able to be expressed almost correctly by the Patterson function obtained from the theoretical I-V curves for the model structure. In the Patterson function obtained from the experimental I-V curves, the locational relation between the atoms of subsurface layer was in agreement with the CsCl type structure. More over, because the faint peak, by which we can distinguish the model, can be seen, it seems that the model B8 is preferable to the model A8. This result is consistent with the model shown by Walter et al. (C) 2008 Elsevier B. V. All rights reserved.