Successfuln‐type doping of HgCdTe layers with indium during growth by molecular beam epitaxy is reported for the first time. The indium concentration is found to increase with the In flux. The doping level reaches around 1018cm−3, which is nearly two orders of magnitude more than what can be achieved by stoichiometry deviation in as‐grown samples. In the range studied, the electrical efficiency is substantial and decreases with increasing In atomic concentration. The experimental measurements are in agreement with a model suggesting that indium, which is not singly ionized, precipitates as In2Te3and that the native acceptor defect concentration remains approximately constant.n‐type doping is shown to be possible for a wide range of alloy concentrations. Good electron mobilities in the alloy are presented for the doping concentrations studied. This technique will greatly enhance the potential of molecular beam epitaxy for device applications of this material.