Abstract: In order to optimize the excavation and support design of underground caverns and address the potential problems of insufficient or wasteful support caused by traditional rock classification methods, this article based on the proposed Akto pumped storage power station, elaborates on the design ideas of tunnel excavation support from the perspectives of surrounding rock classification and block theory, and proposes support schemes and suggestions. Research indicates, the block theory fully considers the unfavorable combinations formed by the occurrence of structural planes, and can intuitively and accurately analyze the movable blocks and key blocks formed on different air faces when cutting different structural plane combinations. Furthermore, the shape of the blocks can be analyzed to determine their stability and required supporting force. In traditional support design, support measures based on surrounding rock classification results may result in support waste when the formed blocks are small; When the formed block is large, it may be difficult to meet the stability requirements of the surrounding rock, and the block theory compensates for this. Through research, this article summarizes the formation of a working mode for underground tunnel excavation and support design, which is mainly based on surrounding rock classification and supplemented by block analysis. The research results of this article will provide theoretical reference for the excavation and support design of the tunnel during the construction period.