The Rijndael algorithm mainly consists of a symmetric block cipher that can process data blocks of 128, 192 or 256 bits by using key lengths of 128, 196 and 256 bits. This work using Rijndael cryptography symmetric algorithm for data encryption/decryption and RSA cryptography asymmetric algorithm for Rijndael key's encryption/decryption. The encryption and decryption of any data has a secure key, which is used for data encryption. For this purpose asymmetric key is used. This work securing the data key using RSA algorithm. Here RSA key size is 128-bytes. This work also generating two pairs of keys; public and private key. Using Public key it encrypts the data key and other one is public and private key pair ,which will send to other person, so that opposite person can decrypt the encrypted key using his public and private key.