We have developed a program for simulating resonant inelastic X‐ray scattering (RIXS), SIM‐RIXS that can be run on personal computers with a Microsoft Windows XP/Vista operating system. RIXS primarily reflects lifetime‐broadening‐suppressed (LBS) or lifetime‐broadening‐suppressed state‐selective (LBSS) X‐ray absorption fine structure (XAFS). SIM‐RIXS can convert theoretical LBS/LBSS–XAFS profiles to RIXS spectra, and it can derive an optimal LBS/LBSS–XAFS profile to reproduce experimental RIXS spectra. SIM‐RIXS has three basic modules, and each user‐friendly graphical user interface enables even novices, who are unfamiliar with RIXS analysis, to use this software. In this software, the first module sets conditions using conventional XAFS data; the second module does the same for conventional X‐ray fluorescence data; and the third module is used for RIXS simulation based on the Tulkki–Åberg equation. An example of its application to the EuLγ4 RIXS of Eu2O3 is presented. SIM‐RIXS can readily provide a basic description of the excitation and emission energy dependence of EuLγ4 RIXS, elucidating the existence of the ‘hidden’ peak at 8056 eV in the Eu(III) L1‐XAFS. This demonstrates the usefulness of SIM‐RIXS in RIXS analyses. Copyright © 2011 John Wiley & Sons, Ltd.