A method of manufacturing an all-solid-state battery electrode, an all-solid-state battery electrode manufactured by the method, and an all-solid-state battery including the electrode are disclosed. In the method, a specific type of binder included in the electrode is prepared in a fiber form by applying pressure to the binder under specific conditions, so that the fiber-form binder thus prepared has an average fineness that satisfies a specific range. Therefore, the all-solid-state battery including the electrode has an advantage of having high capacity even in the case of electrode thickening for high loading.