This disclosure discloses a data judging method applied in a distributed storage system and the distributed storage system. The distributed storage system includes a plurality of processing units and a plurality of storage units corresponding to each processing unit. The data judging method prescribes that a processing unit corresponding to a storage unit that stores preset data is a first processing unit, the storage unit that stores the preset data corresponding to the first processing unit is a first storage unit, other storage units corresponding to the first processing unit except for the first storage unit are second storage units. The data judging method provided by this disclosure may judge whether the preset data needs to be encrypted. Thus, privacy protection may be performed to preset data that needs to be encrypted, without performing encryption protection to all data, thereby being capable of utilizing data reasonably.