The invention discloses a method for restoring copper-polluted soil by plants. The method provided by the invention is characterized in that dayflower seedlings subjected to cutting propagation are planted in copper-containing soil, grow and are harvested or are pulled up during harvest time; and copper is recovered. Concretely, the method comprises the following steps of 1, cutting off stems of dayflower plants, carrying out cutting propagation of the stems by a cutting bed according to plant and row distances of 5cm*10cm, and keeping soil moist after cutting, 2, flattening a sample area in copper-polluted zone, and digging planting holes, 3, planting dayflower seedlings rooting in the cutting bed in copper-containing soil, 4, harvesting overground parts of the dayflower seedlings or pulling up the whole dayflower seedlings with roots, and 5, drying and crushing the harvested overground parts of the dayflower seedlings or the whole dayflower seedlings with roots, and carrying out copper recovery. The method provided by the invention has the advantages of low cost, high restoration efficiency and low environmental risk, and can be utilized for restoration of copper-polluted soil in industry and agriculture and for reconstruction of ecological vegetation in a mine tailing area.