In this study, the synthesis of poly(dibromophenylene oxide)s were achieved via atom transfer radical rearrangement polymerization through decomposition of Bis(2,4,6-tribromophenolato)di(N-methyl imidazole)Cu(II)-Cu(TBP) 2 (NMIZ) 2 , Bis(2,4,6-tribromophenolato)di(N-methyl imidazole)Co(II)-Co(TBP) 2 (NMIZ) 2 , Bis(2,4,6-tribromophenolato)di(N-methyl imidazole)Ni(II)-Ni(TBP) 2 (NMIZ) 2 complexes. Polymerizations were carried out under two different conditions to investigate the effect of time and temperature on percent conversions, intrinsic viscosities. Characterizations of the polymers were performed by FTIR, DSC, 1 H-NMR, 13 C-NMR, SEM and viscometric measurements. The poly(dibromophenylene oxides)s, synthesized by the transition metal complexes, having nonchelating ligand N-methyl imidazole, displayed selectivity in the favor of 1-2 and 1-4 additions, taking place at equal rates irrespective of the type of the metal used. Among the synthesized polymers, the highest percent conversion and intrinsic viscosity was achieved by the decomposition of Cu(TBP) 2 (NMIZ) 2 complex, whereas, Ni(TBP) 2 (NMIZ) 2 yielded the lowest. Investigation of the complexes via mass spectroscopy and the thermal behavior of the by-products enlightened the underlying reasons of the variations at percent conversion and intrinsic viscosity values of the resultant polymeric products.