Memory management method, memory control circuit unit and memory storage device

The invention provides a memory management method, a memory control circuit unit and a memory storage device. The method comprises the following steps: a plurality of super-entity erasing units are arranged, wherein each super-entity erasing unit comprises at least two entity erasing units; a first super-entity erasing unit comprises a first entity erasing unit and a second entity erasing unit which belong to different operating units; the first entity erasing unit and the second entity erasing unit store different parts of first data; and entity erasing units which store the least valid data are selected from each operating unit to execute garbage collecting programs. Therefore, the efficiency of the garbage collecting programs can be improved.