Privacy preservation of data mining has developed as a widespread study area in order to secure the private information over the network. Privacy preserving methods like L-diversity, Randomization, Data distribution, and Kanonymity have been recommended in directive to perform privacy preservation of data mining. The Privacy preservation of data mining (PPDM) methods protects data by masking or by erasing the original sensitive one to be masked. The private data can be preserved efficiently using cryptographic techniques .In our work we propose a modified two fish algorithm with 256 keys as a cryptographic approach to provide security for PPDM