New aryl-Pt(II) complex, including 2,2′-dipyridylamine (dpya) as a bidentate ligand was obtained through the reaction of [(p-tolyl)2Pt(Me2S)2] with 2,2′-dipyridylamine in a 1:1 stoichiometry. The aryl-Pt(IV) complex was synthesized during the oxidative addition reaction of [Pt(p-tolyl)2dpya] with MeI. In these organoplatinum complexes, dpya was bonded to the Pt center via N2 atoms. The MeI was used as a reagent for investigation of oxidative addition reaction (ox. add) on the Pt(II) center, which led to the formation of Pt(IV) complex with octahedral geometry. It was shown that the synthesized Pt(II) and Pt(IV) complexes contain a 1:1 M:L molar ratio. Moreover, conductivity measurements confirmed the non-electrolyte nature of the platinum complexes. These organoplatinum complexes have been characterized by X-ray crystal structure, 1H NMR, FT-IR, conductometry, elemental analysis and UV/Vis spectroscopy. Single X-ray crystal structure showed the asymmetric unit of the Pt(II) complex included one Pt(II) atom, one 2,2′-dipyridylamine and two p-tolyl groups. Furthermore, oxidative addition reaction of iodomethane with Pt(II) complex at 29, 32, 35 and 38 °C was studied and the enthalpy and entropy of activation, activation energy (Ea) and rate constants were calculated.