The invention provides a preparation method and a preparation device for natural plant ocher series pigments, belonging to the technical field of preparation of pigments. The preparation method for the natural plant ocher series pigments comprises the following steps: a, adding water into a container I, and stirring; b, adding a stabilizer into a vessel I, stirring until the stabilizer is dissolved, then adding water into the vessel, heating, and then stirring; c, adding a glue material into the vessel I, stirring until the glue material is dissolved, thus obtaining glue solution, and collecting the glue solution into a vessel II; d, pouring a coloring agent into the vessel II; e, sequentially adding a brightening agent and a preservative into the vessel II, uniformly stirring, then placing, and carrying out association reaction; and f, adding water at the temperature higher than 90 DEG C into the vessel II, uniformly stirring, and standing; and the preparation device for the natural plant ocher series pigments comprises a box body I and a box body II, the vessel I is arranged in the box body I, and the vessel II is arranged in the box body II. According to the preparation method and the preparation device provided by the invention, the natural plant ocher series pigments can be prepared in a more energy-saving and environment-friendly way.