Typically, cloud computing includes the provisioning of dynamically scalable and virtualized resources as services over the Internet. In the cloud environment, based on the user’s needs, various types of services can be delivered that often must be composited to meet the user requests. Therefore, service composition is emerging as a universal technology in order to integrate distributed and heterogeneous services to combine and consolidate the cloud services. This idea focuses on the innovation of a new cloud service including previously existing services for cost and time reducing and efficiency improving. However, to the best of our knowledge, despite the importance of this matter in cloud environments, there doesn’t exist any comprehensive and systematic research and survey in this field. Therefore, the purpose of this paper is to survey the existing techniques and mechanisms which can be addressed in this domain. Briefly, the contributions of this paper are: (1) providing an overview of the existing challenges in a range of problem domains associated with cloud service composition, (2) providing an anatomy of some important techniques throughout scope of cloud service composition and (3) outlining key areas for the improvement of service composition methods in the future research.