Argillaceous rock (clay rock, shale, mudstone etc.) has been considered as favorable host rock types for high-level radioactive waste (HLW) geological disposal, drawing significant attention from nuclear nations in the field of research of geological disposal repositories. Currently, China has entered the stage of constructing granite-based underground laboratories for HLW geological disposal facilities. In order to consolidate the foundation for site selection of disposal facilities for different host rocks in China, the screening process and main progress of clay rock was systematically reviewed. The results show these as follows. The screening of clay rock sites is currently in the planning and site selection stage. Two pre-selected sites recommended in Tamusu pre-selected area in Inner Mongolia could be regarded as pre-selected sites for HLW and medium to low-level waste disposal sites. Different from traditional clay rock, Tamusu mudstone is determined as a new kind of argillaceous rock containing analcime and dolomite. Advantages over engineering construction, preventing nuclide migration and diffusion characteristics are highlighted by Tamusu mudstone. Conducting detailed evaluations on argillaceous pre-selected sections and recommending pre-selected sites, as well as strengthening technical cooperation and talent cultivation, are important approaches and practical requirements for laying a solid foundation for site comparisons. In addition to carrying out researches on Beishan underground laboratory, the management system for HLW geological disposal should be rationalized to ensure the continuity of the two technical routes of granite-based and clay rock based, and to promote innovation development of HLW geological disposal.To provide guiding opinions for promoting the coordinated development of China's HLW radioactive waste geological disposal and consolidating the foundation of site selection for disposal facilities.