Disclosed is a method of providing bio-information data based on a plurality of blockchains. The method includes enabling a user blockchain node to store user block data including user information, a shared key, and a hash key for each user of a plurality of users, enabling an electronic contract blockchain node to store contract block data including contract information for a first user requesting a second user to generate bio-information data, the first user and the second user being included in the plurality of users, enabling a data transfer blockchain node to store transfer block data including storage information for at least one storage server that stores the bio-information data, and delivering the transfer block data from the data transfer blockchain node to the first user.