A formulation containing an A-decarbonized-5α androstane compound for increasing white blood cells and use thereof. The A-decarbonized-5α androstane compound can prevent, alleviate and improve the reduction in the number of white blood cells caused by chemotherapy or radiation therapy, and can be used for preparing a preparation or a composition, the preparation or the composition being used for (a) increasing the number of white blood cells or (b) preventing or treating leucopenia.