Cloud computing technology can be used in all types of organizations. There are many benefits to use cloud storage. The most notable is data accessibility. Data stored in the cloud can be accessed at any time any place. Another advantage of cloud storage is data sharing between users. By sharing storage and networks with many users it is also possible for unauthorized users to access our data. To provide confidentiality of shared sensitive data, the cryptographic techniques are applied. So protect the data from unauthorized users, the cryptographic key is main challenge. In this method a data protection for cloud storage 1) The key is protected by two factors: Secret key is stored in the computer and personal security device 2) The key can be revoked efficiently by implementing proxy re-encryption and key separation techniques. 3) The data is protected in a fine grained way by adopting the attribute based encryption technique. So our proposed method provides confidentiality on data