In the pharmaceutical industry, a large number of low boiling point volatilize organic solvents are used in the process of drug extraction and chemical synthesis. Most of the organic waste gases are collected through organized pipelines, which have high concentration and can be treated by condensation, absorption, adsorption and catalytic combustion. Meanwhile, there are still some unorganized escaping gases, which have low concentration, wide diffusion and difficult collection, which are not conducive to the prevention and control of air pollution and the occupational health of employees. The large gasvolumn and low concentration organic waste gases (taking toluene as an example) were we collected , concentrated by molecular sieve runner, then large gas volumn of condensed and adsorbed .The study provides a treatment route suitable for large gas volumn and low concentration organic waste gas.