As cloud is an emerging paradigm of computing, it throws open various challenges and issues. The major issue hindering the growth of popularity of usage of cloud computing is Cloud security. There are numerous cloud security issues, of which this paper addresses the problem of insecure APIs. APIs act as the interface between cloud provider and the customer and the security of cloud computing depends largely on the security of these APIs. Hence a strong API access control mechanism is required. This paper proposes a two stage access control mechanism implemented at the API level using the Role Based Access Control Model (RBAC).