This work aimed to study a sintered Ni-doped ZnO dilute magnetic semiconductor synthesized by means of a combustion reaction and to evaluate the effect of doping and sintering in the band gap and magnetic properties of the material. X-ray diffraction showed the formation of the ZnO semiconductor phase and also the formation of a second-phase characterized as a solid solution of nickel-zinc oxide. The hysteresis curves showed the success in creating ferromagnetism with doping and the effect of sintering in the remanent magnetization and coercive field values, yet both systems were able to maintain its ferromagnetic behavior. The UV-vis analysis indicated the value of the band gap continued as a semiconductor material, although it has been narrowed. Scanning electron microscopy was used in a complementary way to evaluate the morphology and its effects on magnetic properties.