Cloud computing market is developing rapidly, promoting the requirement of developing cloud applications and cloud service. However, the cloud platform provided by the platform vendor cannot be able to meet the requirements completely, and developers need secondary development, which increases development cycle and reduces the efficiency. OpenStack is an open source cloud computing platform, providing service of computing, storage and networking. Integrating ideas of service oriented architecture and metadata, a development framework of cloud platform based on OpenStack is proposed for development of virtual machine management applications, storage application and custom application. Based on the framework, a virtual machine customization system is developed, which verifies the usability and efficiency of the development framework.