From National Agency for Environmental Impact Control (BAPEDAL), NOx is one of the five parameters that determine the Air Pollution Standard Index (ISPU). It contributes about 10% of total air pollution every year. The NOx can cause severe environmental problems such as global warming, ozone depletion, respiratory diseases and acid rain. To overcome the problems, it is necessary to conduct study on how to reduce the level of NOx gas emissions. This study, therefore, aims to absorb NOx from the air through module membrane hollow fiber using a mixture of HNO3 and H2O2 solutions as absorbent. The feed of gas flowed through the tube side of the module, while the absorbent solution stays in the shell. The independent variables tested were NOx gas flow rate between 100 ml/min and 200 ml/min with NOx gas concentration of 600 pm and H2O2 variation ((0,5, 5, 10 wt.%) reacted with 0.5 M HNO3. Experimental results showed that gas flow rate increases were equal to flux, mass transfer coefficient, absorption efficiency and NOx loading increases. The highest percentage of NOx separation 0f 96.8% occurred at gas flow rate of 100 cm3/minute using 10 wt.% of H2O2 in absorbent solutions.