The present invention relates to a novel compound of 4'-thionucleoside, a preparation method therefor, a pharmaceutical composition comprising the same and an application thereof. Specifically, the present invention relates to a phosphamide derivative of 4'-thionucleoside, a preparation method therefor, a pharmaceutical composition comprising the same, a use thereof in the preparation of a medicine for preventing or treating abnormal cell proliferation diseases (for example, tumors or cancers and related diseases) or virus infectious diseases, and a method of using the same for preventing or treating abnormal cell proliferation diseases (for example, tumors or cancers and related diseases) or virus infectious diseases.