This paper proposes a model to conduct macro-stress tests of credit risk for conventional and Islamic banking in Indonesia based on scenario analysis. The aims are to investigate and to compare the financial system resilience of the two banking systems from various macroeconomic shocks. It used NPL and NPF to measures credit risk of conventional and Islamic banking. It considered several exogenous macroeconomic variables, namely Gross Domestic Product, Exchange Rate, Consumer Price Index, and Interest Rate. It applied the ARDL Model which is estimated for each type of bank credit portfolio that splits into 9 sectors. It found that a decreased in GDP, exchange rate depreciation, an increased in CPI, and interest rates contributed to encouraging a rose in both NPL and NPF levels. CPI was the biggest source of vulnerability to credit risk in both groups of banks, followed by GDP, exchange rates, and interest rates. This evidence indicates that the vulnerability of the financial system in both groups of banks did not only depend on the internal performance in each bank but also depend on the external shocks. It also confirmed that although Islamic banks and conventional banks used different operating systems, they could not be separated from macroeconomic shocks.