Cloud computing is the vast computing utility, where users can remotely store their data into the cloud and have the benefit of the on-demand availability. As cloud computing is having increasing popularity, users have been outsourcing their sensitive data from local computers to the cloud for ease access and reduces cost. To preserve privacy of data, sensitive document has to be outsourced to cloud by encrypting data. Thus auditing an encrypted cloud data is very important. Since cloud consists of the huge number of data users and documents, it is required to audit the data and ensure the correctness of data. In this paper auditing the stored data is done. Auditing is done by introducing a network admin called Third Party Auditor (TPA) instead of owner. TPA has adequacy and expertise to... access and expose the risk of cloud storage services on behalf of users upon request. TPA will be fully automated and will be able to properly monitor confidentiality and integrity of the data. TPA audits the stored encrypted data blocks without retrieval of original data and report to the owner if there is any dishonest behaviours such as deleting, modifying, updating etc. The released audit report helps the user to evaluate the risk of their services.