The utility model discloses a heat exchanger and dryer that has it, wherein, the heat exchanger includes casing and a plurality of heat exchanger fin, the casing has first import, first export, the second import, the second export, spaced apart the arranging of axial of casing is followed to the heat exchanger fin, between two adjacent heat exchanger fins, the heat exchanger fin that lies in both sides respectively and prescribe a limit to a plurality of spaced apart first runners of arranging and second runner between the relative lateral wall of casing, wherein, first runner switches on with first import and first export respectively, the second runner switches on with second import and second export respectively, and the fluid flow of first runner is to the fluid flow with the second runner to cross -counterflow. According to the utility model discloses a heat exchanger through arranging the runner against the current, improves heat exchange efficiency, reduces energy consumption and noise, and consequently, the simple structure of this heat exchanger, simple to operate, heat exchange efficiency and space utilization are high, and move small in noise, low in manufacturing cost.