This article presents the results of the synthesis and physicochemical investigation of a coordination compound formed by lanthanum(III) nitrate and 4-aminobenzoic acid (PABA). The interaction of 4-aminobenzoic acid with lanthanum(III) ions, as well as the conditions for the formation of the coordination compound, were investigated. Modern physicochemical analytical methods were used to determine the composition and structure of the synthesized compound. In particular, changes in the carboxyl and amino groups of the ligand during the coordination process were analyzed using infrared (IR) spectroscopy. In addition, thermal analysis methods were considered for determining the thermal stability of the compound and the stages of its thermal decomposition. The obtained results are important for evaluating the coordination properties of 4-aminobenzoic acid in the formation of coordination compounds with lanthanide ions and for determining their compositional and structural characteristics.