The dynamics of accumulation of electrically active radiation defects under ion doping of epitaxial Cd x Hg 1−x Te films is studied for various distributions of film composition in the implantation region. The epitaxial films were irradiated by boron ions at room temperature in the continuous regime, with the dose ranging within 1011−3·1015 cm−2, energy — 20–150 keV, and ion current density — j = 0.001–0.2 µA·cm−2. It is found that the natural logarithm of the introduction rate of electrically active radiation defects linearly depends on the epitaxial-film composition in the range of mean projected path of implanted ions. An analysis of the experimental data shows that the dynamics of accumulation of electrically active radiation defects is determined by the epitaxial-film composition in the implantation region.