Collecting method for gas/vapor mixture

The invention discloses a collecting method for a gas/vapor mixture. The collecting method adopts a solvent which can dissolve all the components of the gas/vapor mixture to collect. When the unstable high-temperature and high-pressure gas/vapor mixture of which the components are changed with the air pressure and temperature is collected, the solvent which can dissolve all the components of the gas/vapor mixture is adopted to collect to enable all the components in the gas/vapor mixture to be dissolved in the solvent, so that the fact that reactive crystallization and attachment as well as gas-phase loss are prevented during the collection is guaranteed, the gas/vapor mixture in a sample can be fully and uniformly transferred into a liquid-phase solvent during the collection, the fact that the analysis is completed once is guaranteed, further the correctness of data is guaranteed, and reliable data is provided for process control. The method can be used for uniformly converting the high-temperature and high-pressure gas/vapor mixture into stable and weighable liquid state in a dissolved manner, and is an analytical method which is simple, safe, economic, precise and reliable.