Abstract: Access control techniques are the very important aspect of cloud architecture, through which data publishing can be regulated to the legitimate users. But at the same time it should not consume huge computational load which may burden the user. In the conventional approach, the data is encrypted as per the access structure and the user able to decrypt only the attribute set matches. However, they require huge computational requirement in terms of space and processing capability. Problem such as preventing cloud server from learning user access privilege related information is also important. Providing support to a continuously varying user dynamics with dynamic user grant and revocation is essential. In Hybrid RBAC and Chaos Access (HRCA) control mechanism, the control is employed over an already encrypted data. Also, the user is allowed to access the data based on the access structure assigned to his role at the server itself. It will warrant security from non-trustable servers. This scheme is implemented on a three layered approach by separating key manager from cloud server, in order to remove key escrow and arbitrary-state attribute expression parities in existing methods. To ensure greater flexibility in case of emergency, a break-the-glass data access approach also included for data availability without any denial of service. Simulation result shows that the approach derive minimal disk space, processing time, access delay time, energy expenditure and cost than RBAC, MAC, DAC.