p‐type ion‐implantation doping of Al0.75Ga0.25Sb is reported. The surface morphology and electrical properties of Al0.75Ga0.25Sb are shown by atomic force microscopy and Hall measurements to be degraded after rapid thermal annealing of 650 °C. Implantation of Be and Mg results in sheet hole concentrations twice that of the implanted acceptor dose of 1×1013cm−2following a 600 °C anneal. This is explained in terms of double acceptor or antisite defect formation. Implanted C acts as an acceptor but also demonstrates excess hole conduction attributed to implantation‐induced defects. Implanted Zn requires higher annealing temperatures than Be and Mg to achieve 100% effective activation for a dose of 1×1013cm−2probably as a result of more implantation‐induced damage created from the heavier Zn ion. Secondary ion mass spectroscopy of as‐implanted and annealed Be, Mg, and C samples are presented. Diffusion of implanted Be (5×1013cm−2, 45 keV) is shown to have an inverse dependence on temperature that is attributed to a substitutional‐interstitial diffusion mechanism. Implanted Mg (1×1014cm−2, 110 keV) shows dramatic redistribution and loss at the surface of up to 56% after a 600 °C anneal. Implanted C (2.5×1014cm−2, 70 keV) displays no redistribution even after a 650 °C anneal. This work lays the foundation for using ion‐implantation doping in high performance AlGaSb/InGaSb‐basedp‐channel field‐effect transistors.