Abstract:In order to investigate the effects of different application does of selenium (Se) on the contents of total flavonoid, chlorogenic acid and selenium in the flower of Chrysanthemum morifolium, a sand culture experiment was conducted. The results showed that, it promoted the plant growth and increased the contents of total flavonoid, chlorogenic acid, when Se applying doses did not exceed 2.0 mg/kg. The dry weights of flower, stem-leaf, root and the contents of total flavonoid, chlorogenic acid increased with the increase of Se applying doses, the optimal effect was obtained when Se at 2.0 mg/kg. The dry weight of flower, root and the contents of chlorogenic acid of the plants in the treatment of Se at 2.0 mg/kg were significantly higher than Se applications at 0, 0.25, 0.5 mg/kg, and the former’ contents of total flavonoid was higher than Se application at 0, 0.25, 0.5, 1.0, 4.0 mg/kg. Excessive Se applying dose, such as at 4.0 mg/kg inhibited the growth of the plants, the dry weight of flower, stem-leaf, root and the contents of total flavonoid, chlorogenic acid were lower than Se at 2.0 mg/kg. The contents of Se in flower, stem-leaf and root of Chrysanthemum morifolium increased with the increase of Se application doses. The relationship between Se contents in stem-leaf and root of Chrysanthemum morifolium and Se application rate is liner, while the relationship between Se content in flower(y) and Se application rate(x) fits an equation (y = -0.817 5x2 + 6.004 5x + 0.136 3). It showed that the suitable Se applying doses could significantly increase the contents of total flavonoid, chlorogenic acid and Se content in the flower. The above results provide the theoretical basis for the development of Se-enriched Chrysanthemum morifolium and its products.