Cloud Computing plays a main role in present day to day life. Security & privacy of data is major task in cloud. It is required to protect data from hackers & introdures . To provide more security this paper present multi attribute authority Cipher text Attribute Based Encryption (CPABE )technology with multi Central Authority(CA). Due to untrusted cloud server data access control becomes challenging task in cloud computing. Current data access control scheme is no longer applicable to cloud storage system, because it can’t provide fully trusted cloud server. We call it as a central authority. This single CA did not manage any attribute but responsible for issuing user unique id (UID).This CA must have capacity to decrypt any Cipher Text(CT) on the cloud. To overcome such a drawback here we can replace single CA to multi CA.in this paper we design secure cloud storage by providing access to the files using CPABE scheme. This system achieve forwarded & backward security . Also in this paper revocation technique is used related with file,user and attribute.