A data management device includes a memory including a multistage Bloom Filter, a first stage being divided into filter parts of which the number is same as that of data blocks, and a pth stage being divided into filter parts of which a size is a combination of filter parts of a (p−1)th stage; a registration unit registering an entry of data in a filter part of the first stage corresponding to a data block where the data is stored, and the entry of the data to a filter part of the pth stage corresponding to the filter part of the first stage where the entry of the data is registered; and a search unit determining which filter part of the first stage an entry of data being searched is registered in by narrowing down filter parts from the Bloom Filter of which a stage number is large.