<p>The contamination of water and soil with heavy metals such as lead is a major global problem. Heavy metals affect the physiological functions of living organisms, cause cancer, and damage the immune system. Hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂) is one of the most effective materials for the removal of heavy metals from contaminated water and soil. This study focuses on the structural characterization of lead-doped hydroxyapatite synthesized using two different methods: incipient wetness impregnation (IWI) and ion exchange under varying concentrations of Pb(II). Characterization methods such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and thermogravimetric analysis (TGA) were used to understand the incorporation and/or the deposition of lead on the surface of calcined or uncalcined lead-doped hydroxyapatite. The XRD spectra show that for powders doped with more than 0.6% Pb, characteristic peaks of PbO and Pb(NO₃)₂ appear, respectively, with the calcined and uncalcined powders prepared by the IWI method. XRD characterization showed the formation of PbHPO₄ and PbHAP for samples synthesized by ion exchange. These observations were approved by the results of the FTIR, SEM, and TGA analysis. TGA analysis of samples synthesized by IWI method showed the phenomena of dehydration of PbHPO₄, decomposition of lead nitrate, and formation of [Pb_<i>x</i>Ca_5−<i>X</i> (PO₄)₃OH]. SEM micrographs show a crystal in quadratic form characteristic of the litharge (PbO). The crystal appears elongated, with a size close to 8–10&#xa0;μm in length and a few hundred nanometers in width. Thermal analysis of samples synthesized by ion exchange showed possible dehydration of PbHPO₄ and decomposition of lead nitrate. The results of this study confirm that hydroxyapatite doped with Pb(II) ions by dry impregnation or ion exchange constitutes an alternative for the decontamination of water and soil polluted by heavy metals.</p>