The widespread implementation of Business Process Management (BPM) strategies has increased the demand for an integral approach to business process modeling, in which all stakeholders can effectively participate and together shape a company’s business processes. Amongst others, this demand was a basis for the development of the Business Process Modeling Notation (BPMN) as a proposed industry standard. It does not only provide technical advantages such as a support for serviceoriented computing, but also claims to be readily usable for business users. Following this presumption, BPMN is even used by the Object Management Group (OMG). It adopted BPMN instead of the Activity Diagram (UML AD) as the core standard to create a business modeling framework. For companies, however, changing to a new process modeling language is a significant expense factor. Furthermore, consolidated findings on whether BPMN is indeed more usable for business users than UML AD are missing. In this paper, we present results from a comprehensive empirical comparison of both languages, in which we examined the application by business users during a model creation task. Results indicate that the UML AD is at least as usable as BPMN, since BPMN did neither differ significantly in effectiveness, efficiency, nor user satisfaction.