A multilevel cache-based data read/write method and a computer system. The method includes acquiring a query address of a physical memory data block in which data is to be read/written, acquiring a cache location attribute of the physical memory data block, querying whether a cache is hit until one cache is hit or all caches are missed, where the querying is performed according to the query address in descending order of levels of caches storable for the physical memory data block, and the levels of the caches are indicated by the cache location attribute, and if one cache is hit, reading/writing the data in the query address of the physical memory data block in the hit cache; or, if all caches are missed, reading/writing the data in the query address of the physical memory data block in a memory.