The organ donation and transplantation supply chain - ODTSC is a complex and multi-professional system with donors, organs, recipients, and waiting families on the upstream chain side and transplanted patients, and their families, on the supply chain downstream side. Health professionals must coordinate and streamline the donation, transplantation, and transplanted patients' care, as the 3 main processes in the ODTSC. These processes have been improving in several countries, but the global demand for donated organs is nearly 1,3 to 2 million and the transplantation capacity is below 150,000 surgeries. The research was motivated by low performance when comparing Rio de Janeiro data from 2021 and 2022 to benchmarks and its main objective was to improve practices by analyzing the ODTSC and its process and data. Process mining - PM has been evolving from a process and data science topic to a useful technology related to production engineering. In health services, the hospital environment, health production systems, and society benefit from PM utilization with a new way to increase value. Discover the variants, checking the conformance to regulations, analyzing causes, and proposing improvements are PM techniques used to enhance performance and reduce the gap between organ demand and supply. The data was used to analyze the process design, the data itself, and indicators by applying PM techniques and using a tool. The methodology was based on the design research and multiple studies cases methods with a bibliographical review - and no previous work was found, demonstrating the novelty of this research; PM tools selection, data preparation; and interviews to identify improvements. With the study, it was possible to demonstrate the applicability of PM, and an increase of 15 % in organs donated in Rio de Janeiro ODTSC was observed.