Abstract: The flow field design in the pressurized module of target spacecraft is a basic step for the temperature and humidity control and the contaminant diffusion, and it is important for the thermal comfort of astronauts working for a long term in orbit. An isothermal experimental scheme for the flow field ground test is proposed in this paper and the flow field design is validated in the ground test by keeping the air temperature in the flow field zone with variations not more than 1℃ so that the effect of the natural convection can be neglected. The tested air velocity in 88.3% of the astronaut working zone takes values between 0.08～0.5 m/s and between 0.08～0.12 m/s in the sleeping zone. The flow field design for the microgravity condition is successfully verified by ground tests. The percentage of the optimal air velocity in the range 0.076～0.203 m/s in the target-spacecraft flow field is up to 82.8%, which is better than that in the International Space Station modules.