The oil droplet and powder in gas will caused serious damage to the equipment in the processes of dry gas seals, long-distance transmission of natural gas and large rotating machinery crankcase ventilation, the filter test under atmospheric pressure cannot accurately show the filter performance. According to the ISO-12500 standard, a performance testing system of compressed air filter was established, the experimental operating pressure can be adjusted from 0.1 MPa to 0.7 MPa. The effects of operating pressures on lipophilic and oleophobic filter’s liquid distribution, saturation and pressure drop were analyzed. The results showed that the pressure had a significant effect on the initial pressure drop, liquid migration and saturation of the oleophobic filter. When the operating pressure rose 0.2 MPa, the initial pressure drop of the filter rose by 0.32 kPa, the wetting pressure drop of the filter element (the difference between the equilibrium pressure drop and the initial pressure drop) fluctuated between 4.5 kPa and 5.1 kPa under each operating pressure. Compared with 0.1 MPa, the saturation of the last layer increased by 71% under 0.7 MPa. The number of small wetting area increased and there was a short jump stage before the pressure drop reached equilibrium under 0.7 MPa, this may aggravate the re-entrainment of the filter element, resulting in an increase in the number of droplets in the downstream pipe of the filter, reducing the efficiency of the filter. Influence of operating pressure on the initial pressure drop of lipophilic filter was remarkable, when the operating pressure rose 0.2 MPa, the initial pressure drop of the filter rose by 0.39 kPa. Operating pressure had little effect on fluid migration and saturation, each layer had the same filter saturation distribution, liquid distribution under different operating pressure.