In recent years, enterprises try to develop the online sales systems in order to reach various customers in different places and expect to bring better profit or company exposure via the internet and mobile device channels. However, different platforms, technologies, transaction rules, policies and processes have resulted in data dispersion and business logic inconsistency that is hard for the company to audit and manage. This study presented a service-oriented analysis and design of the online sales process integration for our case company. We analyzed and modeled the processes using the service-oriented modeling and architecture (SOMA) approach to identify service candidates, and also utilized service component architecture (SCA) to create web services for activities required for the processes. Based on the function of services, business rules and logic, the corresponding service abstraction layer of the integrated online sales process is established. Finally, this study used the Business Process Execution Language (BPEL) to realize the service orchestration and composition, thus achieving service reusability. With the SOA solution, the case company can efficiently integrate resources and that the enterprise system become more flexible, agile and cost-effective.