The work reported in this paper aims at a better understanding of the magnetic doping effects on the structural and electrical properties for a series of YBa₂(Cu_1-xCo_x)₃O_7-δ ceramics. The Co doped YBa₂Cu₃O_7-δ are (YBCO) prepared by conventional solid state reaction method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), differential thermal analysis (DTA) and resistivity measurements. The crystal lattice parameters are found to change due to the cobalt doping and tendency to a structure phase transition from orthorhombic to tetragonal, which is confirmed by the decrease of the degree of orthorhombicity. The morphology examination with SEM revealed gradual increases of grain size with x = 0.02 Co, a high porosity is observed in the doped samples compared to the pure one. The decomposition temperature of YBCO is pushed from temperatures above 975°C to lower temperatures of 945°C. The resistivity measurements of doped samples with x = 0.04 and 0.06; shows a deviation in from T-linear behavior due to the opening of a pseudogap.