Data reading method, memory storing device and controller thereof

The invention discloses a data reading method, a memory storing device and a controller thereof. The data reading method is used for a rewritable nonvolatile memory module, wherein the rewritable nonvolatile memory module has a plurality of entity pages. The data reading method comprises the steps of dividing the entity pages into a plurality of entity page groups and setting a corresponding valve value voltage group for each entity page group. The data reading method further comprises a step of reading data from the entity pages of the entity page groups by the corresponding valve value voltage groups. The data reading method further comprises a step of updating the valve value voltage group corresponding to an entity page group in case that the data read from one entity page of one entity page group cannot be corrected by an error correcting circuit. The correctness of the read data can be effectively ensured based on the data reading method.