The increasing level of competitiveness and pressure to which companies are subjected today has led to a greater demand for quality management certifications that validate their processes. For this, the need to continuously analyze, improve, and standardize all the business processes involved becomes urgent. Business process management (BPM), which includes modeling, appears as a response to that need, often leading to processes dematerialization. However, standardization alone is not enough to increase a company's competitiveness. It is necessary to combine continuous improvement through the use of Lean tools, once they are suitable for identification and, consequently, for the elimination of waste and non-added value activities (NVA). This work appears with this need, having as objective the proposal of a methodology that combines the concepts of Lean and BPM, using for the process’s representation the notation BPMN 2.0 (Business Process Model and Notation). The methodology was tested in a case study that involved a newly-created company belonging to the plastics industry and the results contributed to the preparation, initialization, and conclusion of the certification process with the quality standard, ISO9001: 2015.