Disclosed are a Cache partitioning method and device, which relate to the field of electronic information technology, and can flexibly allocate physical memories and Cache Sets for executive entities, thereby reducing interference generated by a plurality of executive entities in the usage of a Cache and improving the performance of memory access. The method comprises: allocating, by an operating system, a physical memory to an executive entity (101); and selecting one or more unoccupied Cache Sets from Cache Sets included in a host, caching data from the physical memory allocated to the executive entity into the selected Cache Set, and establishing a correlation between the physical memory allocated to the executive entity and the selected Cache Set (102). The method is suitable for a scenario where an appropriate Cache Set is allocated to an executive entity.