Index generating and searching method for encrypted field of database

The invention relates to a method for indexing the encrypted field for privacy reasons from a database and data retrieval method using the same. Indexing of the encrypted fields, and the search method according to an embodiment of the present invention, but building an encrypted without saving by decoding the contents of the encrypted field data as an index, the reference value previously set with the encrypted data when building indexes and build an index using the distance information and calculates the distance value of the reference value even during search and search compared with the index information table to build them. In particular, the present invention can minimize the search time by a set composed of sub-leaf node to a leaf node in this case that there is no redundant data.