We fabricated CoFe2O4 (CFO) nanofibers (NFs) and nanoparticles (NPs) via electrospinning and the conventional sol-gel process, respectively. Sizes of these nanomaterials can be controlled by adjusting the annealing temperature. Magnetic dynamic behaviour showed differences between them. These differences have been linked to specific size and shape configurations. At room temperature, magnetic properties were size dependent, but the specific shape configuration dominated the magnetic properties at 5 K.