With the growth of intensified information, the study of cloud resource management becomes a hot topic, since the utilization of the cloud computing can generate powerful online resource convergence. To effectively utilize resources, a new cloud computing resource allocation model based on combinatorial double auction mechanism (CDA-CCRA) is developed. The CDA-CCRA can satisfy the requirements of users and providers simultaneously and reduce the amount of transaction significantly. Simulation results show that the CDA-CCRA model works well in resource allocation under cloud computing environment.