Ni electrodeposits of thickness values ranged from 70 nm till about 1.20 μm and grown on gold substrate by cathodic voltammetry (C-V) technique are investigated varying the scan rate (r) of the related (C-V) curves in the interval 0.167<r<1.67 mV/s. The system engenders thinner films having rougher surfaces for higher r values while lower ones leads to thicker and smoother samples. Their magnetic reversal is ruled by the domain wall (DW) nucleation and motion. Their ferromagnetic-topography dependence reveals the existence of a critical thickness dc∼375 nm for both their microstructure and magnetic nanostructure. Their magnetic domain sizes (w) evolution with the sample roughness is typical of the Bloch domain type (MD)B below dc while the Néel type (MD)N appears beyond dc according to the topography-based model of Zhao etal [J. Appl. Phys. 89, 1325 (2001)]. The magnetic anisotropy of the Ni samples exhibits a predominant parallel component for the thinnest sample while the perpendicular one grows with the thickness increase.