The invention relates to a system for evaporation and concentration by using waste heat of a dryer. The system comprises a first tube bank dryer, a second tube bank dryer and a third tube bank dryer which successively heat materials in series, the exhaust gas outlets of the tube bank dryers are respectively connected with the air inlets of a first cyclone dust collector, a second cyclone dust collector and a third cyclone dust collector, the air outlets of the first cyclone dust collector and the second cyclone dust collector are connected with the air inlet of a waste heat absorption tower, the air outlet in the top of the waste heat absorption tower is connected with the inlet of an absorption tower exhaust fan, a filler layer is arranged at the upper part of an inner cavity of the waste heat absorption tower, a liquid distributing tray is arranged above the filler layer, a water collecting tray is arranged at the bottom of the waste heat absorption tower, the drainage outlet in the bottom of the water collecting tray is connected with the inlet in the middle of a waste heat flash tank, the waste heat flash tank steam outlet in the top of the waste heat flash tank is connected with a flash steam pipe, the bottom of the waste heat flash tank is connected with the inlet of an absorption tower circulating pump, and the outlet of the absorption tower circulating pump is connected with a water replenishing pipe in the center of the liquid distributing tray. The system for the evaporation and concentration by using the waste heat of the dryer disclosed by the invention is high in utilization rate of the waste heat and good in concentration effect.