Abstract: A carbon dioxide capture system comprises a carbon dioxide absorption unit, an ammonia absorption unit, a carbon dioxide stripper unit, an ammonia stripper unit, a heating unit, and a condensing unit. The carbon dioxide absorption unit interconnects with the ammonia absorption unit; the carbon dioxide stripper unit interconnects with the ammonia stripper unit, whereby a first regeneration agent of the carbon dioxide stripper unit and a recirculated ammonia-rich liquid of the ammonia absorption unit directly flow into the carbon dioxide absorption unit to assist a first absorbent to absorb carbon dioxide, and whereby the heat energy generated by the heating unit is more efficiently used by the carbon dioxide absorption unit, the ammonia absorption unit, the carbon dioxide stripper unit, and the ammonia stripper unit. Compared with the conventional carbon dioxide capture system, the present invention has advantages of low power consumption and low equipment cost.