The invention discloses a block management method which is suitable for managing a flash memory chip with a plurality of block surfaces, wherein each block surface is provided with a plurality of physical blocks. The block management method comprises the step: configuring a plurality of physical units, wherein each physical unit comprises a physical block in each block surface and the physical blocks in all the physical units can be simultaneously operated. The block management method also comprises the step: judging whether a main machine system updates all the physical blocks in the physical units or not when data are written into the physical units by the main machine system, wherein the data are written in the storage mode of a single block surface when the main machine system does not update all the physical blocks in the physical units. In addition, when the main machine system updates all the physical blocks in the physical units, the data are written in the storage mode of multiple block surfaces, wherein the physical blocks for writing the data can be simultaneously operated.