The Deep-sea Extremophiles Sampling System, which contents plaited filter, is modeled and simulated in high pressure seawater environment by AMESim software. The dynamic performances of the system under different environment pressures are analyzed and some experiments are done to validate the simulation model. According to the simulation and experimental results, the environment pressure has very little influence on the pressure drop and flow characteristics of plaited filter. The plaited filter performs perfectly in high pressure seawater environment. The deep-sea extremophiles sampling system can meet the requirements.