An electrolysis electrode and a preparation method therefor, an electrolysis apparatus, and a clothing treatment device. The electrolysis electrode includes a substrate, a transition layer, and an electrode catalytic material layer, and the transition layer is attached to the surface of the substrate, the electrode catalytic material layer is attached to the surface of the transition layer, and the thickness of the transition layer satisfies that: electrons can pass through the transition layer. The transition layer of the electrolysis electrode is relatively thin, so that electrons can pass through the transition layer due to a quantum tunneling effect, and thus the electrocatalytic performance of the electrolysis electrode is basically not affected. Furthermore, the transition layer plays the role of transition connection, and can greatly improve the phenomenon of cracks in the electrode catalytic material layer.