Capital adequacy is an important standard, a measure of safety and soundness for banks and financial institutions. Determining capital adequacy is the bank's adjustment of capital levels so that it can absorb all unexpected losses arising in the future and ensure the safety of fixed assets. Maintaining the capital adequacy ratio at an appropriate level will help the bank both effectively use capital and maintain a safe operation. To measure the influence of macro indicators on capital adequacy, we use panel data of 28 commercial banks operating in Vietnam during the period 2007 to 2020. For the most reliable measurement results, the study used the generalized method of moments (GMM). The analysis results show that macroeconomic factors such as inflation, interest rates, GDP growth have opposite effects on CAR. Meanwhile, the VND/USD exchange rate has a positive impact on CAR. The results of this research will help managers have more scientific basis to come up with appropriate governance strategies for their banks.