The present invention relates to a composition for increasing the milk production of livestock, containing Artemisia capillaris as an active ingredient. More specifically, relates to a composition and a feed additive for increasing the milk production of cows, containing Artemisia capillaris as an active ingredient, and a composition and a feed additive for reducing the number of somatic cells in livestock milk, containing Artemisia capillaris as an active ingredient. The composition can increase milk production of animals, and, in addition, can reduce the number of somatic cells in milk being produced, thus enabling production of good quality milk.