The effect of an applied magnetic field on the growth patterns of Zn electrodeposits on filter paper was investigated using an optical microscope and an atom force microscope. It was found that the concentration of electrolyte and the fibre of filter paper influenced strongly the morphology of Zn electrodeposits obtained in unsaturated electrolyte. No evidence indicated that the magnetic field affected the morphology of electrodeposits obtained in unsaturated electrolyte. The branches of Zn electrodeposits obtained in saturated electrolyte grew in two layers, and the thin layer that adhered to the filter paper grew faster than the thick layer. In the case of saturated electrolyte, the 0.40T magnetic field made the branched electrodeposits grow into a spiral pattern. On the basis of these experimental results and the related theories, it was proposed that the magnetic field influenced the morphologies of the branched Zn electrodeposits grown on filter paper through the Hall effect.