Abstract: According to the situation that there are no instruments for regular monitoring of particle matter size in gas pipelines, an automatic sampling skid for particulate matters in gas pipelines have been developed, which can carry out sampling for particle matters in gas pipeline in a safe, reliable and regular way without manual intervention. The device was applied to a gas compressor station of in inland gas pipeline to determine the characteristics of particle matters in inlet pipeline of the station. The mass concentration and particle size distribution of the particle matters were obtained, the mass concentration range was from 2.57 to 7.24 mg/m³ and particle size range was at 1.55 to 21 μm. The size distribution of trapped particulate matters are verified with a scanning electron microscope (SEM) with a sound consistent results. The monitoring results can provide guidance to the preparation of pigging operation plans and adjustment for the operation plan of separation and filtration equipments.