The invention provides a gas environment generating bag for growth of microaerophilic bacteria. The generating bag is composed of a gas impermeable bag I, a gas impermeable bag II, a gas permeable bag I and a gas permeable bag II. The gas permeable bag II is arranged in the gas impermeable bag II and is sealed. The gas impermeable bag II and the gas permeable bag I are both arranged in the gas impermeable bag I and are sealed. The gas permeable bag I is filled with a chemical substance for absorbing oxygen. The gas permeable bag II is filled with a chemical substance that generates CO2 and H2. The generating bag is free of addition of any substances or catalyst during use, a reaction can be carried out just by opening the outer package, so that the generating bag is convenient to use. The generating bag also can generate a less amount of H2 when consuming oxygen to generate CO2, thus further promoting the growth of the microaerophilic bacteria. The reaction process is free of generation of harmful substances that damages human body and pollutes environment.