The effect of the oxygen evolution reaction (OER) is important in water splitting. In this work, we develop sphere-like morphology spinel oxide CoFe₂O₄/NF by hydrothermal reaction and calcination, and the diameter of the spheres is about 111.1 nm. The CoFe₂O₄/NF catalyst exhibits excellent electrocatalytic performance with an overpotential of 273 mV at a current density of 10 mA cm⁻² and a Tafel slope of 78 mV dec⁻¹. The cycling stability of CoFe₂O₄/NF is remarkable, and it only increased by 5 mV at a current density of 100 mA cm⁻² after 3000 cycles. Therefore, this simple method to prepare CoFe₂O₄/NF can enhance the OER properties of electrocatalysts, which makes CoFe₂O₄/NF a promising material to replace noble metal-based catalysts for the oxygen evolution reaction.