The invention discloses a preparation method for an aerated concrete ecological flowerpot. The method comprises the following steps: bottom ashes, grinded fine sand, lime and aluminum powder are mixed with water and stirred to slurries in good mobility after household garbage is burned and used for generating electricity; the slurries are injected in a flowerpot mold for containing a steel wire gauze frame, and then static stop, gas forming and solidification molding are conducted to the flowerpot mold, and precuring is conducted; the mold is removed after precuring, and trimming, decoration and coloring are conducted to the flowerpot mold; and the aerated concrete ecological flowerpot is obtained after high-pressure steam curing cooling. According to the preparation method for the aerated concrete ecological flowerpot, inorganic waste is utilized to product the flowerpot, consumption of natural resources is reduced, and therefore the flowerpot is low in cost. Waste is utilized, pollution to the environment is reduced, and the environment is beautified. The flowerpot is light in weight and convenient to carry and has great porosity, water receptivity and water storage rate, an ecological environment beneficial for breath and growth of plants is created, and therefore the flowerpot is beneficial for growth of the plants.