This study investigates the impact of liquidity on bank profitability. Particularly, bank profitability is measured by return on assets (ROA) while liquid assets to total assets (LATA) and total loans to total deposits (TLTD) are indicators of bank liquidity. A panel data of 26 Vietnamese commercial banks are obtained over the period 2013-2018. The GMM estimation is adopted to test the significant effect of liquidity on profitability of Vietnamese commercial banks. The results reveal that profitability (ROA) was negatively influenced by liquid asset ratio (LATA) and positively correlated to loan-to-deposit ratio (TLTD). Further, bank profitability was also affected by macroeconomic control variables like economic growth (EG) and inflation (INF). The results are not only essential for bank managers but also provide scholars a valuable reference.