Against the backdrop of global challenges and unprecedented events, intellectual capital is seen as the key to opening doors for banks to achieve competitiveness. Inspired by this issue, the paper explores the relationship between intellectual capital and one of the most important functions of banks, namely financial intermediation. The study uses the balanced panel data of 26 Vietnamese commercial banks collected directly from their audited financial statements between 2006 and 2020, and employs various regression analyses such as OLS, Fixed-effect, and the GMM method, in which the VAIC model is utilised as the measure of the intellectual capital of banks. The consistent evidence demonstrates that intellectual capital plays a key role in fostering this function of banks. Also, when dividing VAIC into three components, the empirical result indicates that capital employed efficiency is the most effective resource to enhance financial intermediation compared to human capital efficiency and structure capital efficiency. Furthermore, these findings seem to be clearer in small banks than in large ones, and remain unchanged during both crisis and non-crisis periods. Besides, in the crisis period, the evidence suggests that banks should strengthen their human capital efficiency, and structure capital efficiency should be taken into consideration. Therefore, this study provides a deep insight into the influences of intellectual capital on banking operations in emerging countries, where the development and sustainability of banks could ensure economic growth.