People pay more and more attention to the air quality in the passenger cabin when they are flying. If the concentration of particles in the cabin exceeds the limit, it will cause harm to human health. Therefore, in the design of aircraft ventilation system, it is necessary to consider the constraints of cabin particle concentration limit on the system design. Inhalable particulate matter includes coarse particulate matter PM10 and fine particulate matter PM2.5. Taking a civil aircraft as the research object, this paper proposes an evaluation method of particulate matter concentration in the cockpit. By investigating the relevant technical documents at home and abroad and analyzing the index balance, the limit of particle concentration balance index was obtained. Taking the comfort value as the design requirement, the requirement compliance of the design scheme of a civil aircraft ventilation system was evaluated. The results show that the stable concentration of particulate matter in the cabin is independent of the cabin volume and ventilation volume, and the stable concentration of PM2.5 in the cabin is 31.5 μg/m3, PM10 is 51.75 μg/m3. In order to meet the design requirements of comfortable environment for particulate matter in cabin, it is necessary to add filters. According to calculation, when the recirculation filter is not installed, the minimum efficiency limit of the bleed air filter is 5.5%; when the bleed air filter is not installed, the minimum efficiency limit of the recirculation filter is 26%.