The reflection of X‐rays from a semi‐infinite water target, for energies used in X‐ray diagnostics, is treated by the analog Monte Carlo simulation. In the developed procedure it was possible to calculate separately contributions of photons scattered, before reflection, fixed number of times with target electrons. It turned out that multiple collision type of reflection dominates at all energies investigated, whenever the absorption is small. The same process was also treated analytically as the classical albedo problem for isotropic scattering without energy loss. Very good agreement of results of the two approaches is obtained. © 2003 American Institute of Physics