Conjugated microporous polymers (CMP) synthesized using homocoupling polymerization reactions were investigated as adsorbents for the removal of volatile organic compounds (VOCs) from gas streams. The nitrogen adsorption and desorption data revealed that the resultant CMPs possess a micro/mesoporous structure. The results of the static water vapor adsorption experiment indicated that CMP-50 has a more hydrophobic surface than does commercial activated carbon (AC). The adsorption and desorption performance of benzene on CMP-50 under static and dynamic conditions were investigated, and compared with AC. It was found that CMP-50 has high adsorption capacity under wet conditions (RH = 80%) and fast adsorption kinetics. Moreover, the presence of water vapor in the gas stream had little effect on the adsorption capacity. Taken together, it is expected that materials of the same type as CMP-50 would be promising adsorbents for the removal of VOC vapor from humid gas streams.