During the past three decades, data envelopment analysis (DEA) has been successfully used for measuring the relative efficiency of financial or non-financial firms. This paper presents an empirical investigation to measure the relative efficiency of five Canadian banks versus 6 US big banks using DEA method. The study considers the number of employees and total assets as input and net revenue is used as the output of the DEA model. The data are collected from the official statements of the banks for the fiscal year of 2017. The results indicate that 6 US banks maintained an average efficiency of 0.87 but the average efficiency of Canadian banks was 0.72. While two US banks maintained an efficiency of one, the other US banks demonstrate relatively well in terms of the performance. In Canada, while one bank performed relatively well, the performance of the other Canadian banks were not as good as the US banks.