Social networks are online applications which allow its users to connect by various link types. Online social networks, such as Facebook, LinkedIn are progressively utilized by many people. Facebook is a general-use social network, which allows their individual users list their favorite activities, and soon. But some of the information revealed is meant to be private. However, privacy concerns can be used to prevent these efforts. This paper leads for privacy-preserving social network data mining, which is the discovery of information and relationships from social network data without violating privacy.