Enterprise resource planning (ERP) is a business process management system in which integrated applications are used to manage business processes in a shared data environment. ERP systems usually deal with the two types of business processes, i.e., exchange and conversion. In the exchange process, economic resource, such as product, exchanges to another economic resource, such as the sales process. In a conversion process, an enterprise consumes resources in order to produce new resources, such as the distribution process. Generally, the communication between ERP applications, based on the conversion and exchange processes, is accomplished through Web services. In this context, the implementation of Web services in ERP systems is a complex task. To manage this, the business process model and notation (BPMN) are frequently utilized to simplify the development of ERP applications. However, state-of-the-art BPMN approaches usually deal with the modeling of exchange processes without considering the conversion process. Furthermore, the model transformation solution to automatically generate Web services from the BPMN models are hard to find in the literature. Therefore, in this paper, a novel framework is proposed that supports the modeling of both exchanges as well as conversion processes through BPMN. Particularly, a modeling approach is introduced to represent the ERP processes through BPMN concepts. Subsequently, the rules are developed to convert source BPMN models into target Service-oriented architecture Modeling Language (SoaML) models. Finally, transformation rules are developed to generate fully functional executable Java Web services from SoaML models. As a part of the research, a complete open-source BPMN to Web services transformation (B2W) tool is developed to automatically generate the Web services from the high-level BPMN models. The proposed framework is validated through multiple case studies. The experimental results prove that the proposed framework accurately generates Web services from the BPMN models, which eventually helps in developing the ERP systems with simplicity.INDEX TERMS Model-driven engineering (MDE), business process model and notation (BPMN), service oriented architecture (SOA), ERP systems, service generation.