The article presents a benchmarking of bank's business processes as a method of improving the quality of services provided to the external and internal customers of the banking institution. The article is composed of four parts. The first one includes a description of benchmarking against the background of other means used by the management of the banking institution in order to improve the quality of provided services. In the second part the types and models of benchmarking in the banking sector have been presented. The third part of the article presents the process of introducing the benchmarking of the bank's business processes. In the fourth and final part of the article the benefits of applying the analysed method in a banking institution have been presented. The article enables the lecturer to get acquainted with the benchmarking of bank's business processes which is a modern method attractive for the banks that want to improve the quality of their services.