Paradigms of Cloud computing are gaining prevalent acceptance due to the numerous benefits they provide. These comprise cost-effectiveness, time savings and effective deployment of computing resources. However, privacy and security issues are among the major hindrances holding back the widespread adoption of this novel technology. In this context, enhancing the security of cloud computing demands the highest priority based on the popular encryption method RSA, Genetic Algorithm (GA), and 3D Quick Response (QR) code using MAC address. This paper will show an approach of amplifying the security of cloud computing. Therefore, we are proposing advanced two-step security mechanism of cloud computing. Firstly, RSA is used to provide initial protection of the first stratum. RSA approaches message as input to the hash function and generated hash values is encrypted by using generated sender key. And the receiver will generate a hash code and decrypts the message using the sender's public key. Finally, The Genetic algorithms (GA) are generalized search algorithms based on the mechanics of natural genetics. GA maintains a population of individuals that represent the candidate solutions. After successful completion of Genesis, mutation and crossover GA will provide a framework to match the desired pattern. Moreover, a media access control address (MAC address) of a device is a distinctive identifier assigned to network interfaces for communications at the data link layer of a network segment. In this context, the MAC address is used to generate the 3D Quick response code for user verification. Through experiments, we affirm that the combination of GA and 3D QR Code approach with RSA for two-step security mechanism shows strong potential to heighten the security of Cloud Computing.