One of the key tasks of production management is to reduce the percentage of defects in finished products. The quality management system audit procedure acts as an assistant in solving problems in this area. Hence, the main purpose of the quality audit arises – to collect objective evidence that will identify inconsistencies in processes, products (services) or the quality management system. The main result that a quality audit should lead to is the identification of opportunities for improvement in the work of the organization, therefore, objective evidence that auditors discover during the quality audit is essential in any quality audit. However, while designing complex information systems, analytical methods are often of little use due to the large dimension and complexity of the resulting systems.  Therefore, simulation models are widely used for systematic and independent analysis, which makes it possible to determine the conformity of activities and results in the field of quality with planned activities, as well as the effectiveness of the implementation of measures and their suitability for achieving the goals set, in the field of quality audit. Petri nets have been used to simulate one of the software production processes for the purpose of analyzing, improving, and configuring it, namely, the quality audit process. The improvement of the quality audit simulation will improve the regulations used and thereby improve the quality of products.