Poly(1,2-diaminobenzene) (1,2-DAB) and poly(1,3-diaminobenzene) (1,3-DAB) have been synthesized by using ammonium persulfate as oxidizing agent in the presence and in the absence of the following metal ion salts: CuCl2, NiCl2, and COCl2 with different HCl concentrations. The products showed a different, content of the metal ion depending on the HCl concentration. The polymers were characterized by Fourier transform infrared (FTIR), ultraviolet-visible (UV-Vis) spectroscopy, thermal analysis, and electrical conductivity. The polymerization yield depended on the presence of metal ions that can react as oxidizing reagents and/or catalysts. The polymerization mechanism depended on the position of the substituent. For poly(1,2-DAB) a ladder-type structure was obtained, and for poly(1,3-DAB) one similar to that of polyaniline. The thermal stability increased as the metal ion content in the polymer matrix increased. The electrical conductivity of the polymer did not depend on the metal ion content in the polymer.