Cloud computing presents a new approach to allow the development of dynamic, distributed and highly scalable software (e.g., networks, servers, storage, applications, and services) that can be rapidly supplied and allowed us with minimal management effort or service provider interaction. Cloud computing provides many advantages to its customers but failing to solve information security concerns. Strong encryption with key management is one of the core mechanisms that Cloud Computing systems should use to secure data, so key management is an important technology that can help secure applications and data in the cloud. In this paper, a proposed elliptic curve based distributed key generation (ECDKG) scheme for Transient Clouds is presented. Performance analysis showed that this scheme not only has strong security, but also has less computational and communication costs.