The invention relates to a new crystal form of dolutegravir sodium. Compared with a known crystal form of the dolutegravir sodium, the new crystal form disclosed by the invention has one or more beneficial properties, such as good stability in water, high dissolubility, difficult moisture absorption, good storage stability and good particle shapes. The invention also relates to a preparation method of the new crystal form of the dolutegravir sodium, a pharmaceutical composition of the new crystal form and application of the new crystal form in preparation of a medicine for treating and/or preventing HIV-1 infection.