In recent years, enterprises of different sizes are faced with the challenges of efficiently integrating their business functions and associated systems. With the advent of service-oriented architecture (SOA), these enterprises are exploring the development of business integration solutions based on SOA. A service is defined as a particular business or IT function that is accessible by independent users and systems through a standardized interface. With their very nature, the results of using a business or IT service can be non-deterministic, i.e., one can?t predict ahead of time the outcomes of invoking a business or IT service. For instance, a business service might provide a result short of the original expectation, which would require the use of another business service to compensate for the shortfalls. In this paper, we are going to propose a framework for service-oriented business integration under uncertainties. In this framework, we are going to describe how to achieve better business and IT integration results by composing a set of appropriate business and IT services through a service composition model with uncertainties. The framework will furthermore provide a structure of how the service composition model with uncertainties can be established and maintained.