The development of a new complex absorbent comprising propylene carbonate, tertiary amine and a few activators is introduced. The absorption and regeneration performance of the new absorbent, as well as the corrosive performance and viscosity, have been elaborately determined. Experiments show that the new absorbent, compared with propylene carbonate, exhibited larger absorption capacity, higher absorption rate, higher purity of gas, and no corrosive effect on equipment. The current propylene carbonate washing process for CO2 can be improved by using the new absorbent.