A clothes dryer comprising: a cabinet forming an outer appearance; a drum provided inside the cabinet to accommodate clothes therein; and a heat exchanger (120, 140, 1312) to remove moisture from the clothes accommodated in the drum or to generate hot air, wherein the heat exchanger (120, 140, 1312) comprises: a copper pipe (121, 141) forming a refrigerant circulation passage; and a plurality of fins (122, 142) arranged at positions spaced apart from each other along one direction, and coupled to an outer circumferential surface of the copper pipe (121, 141), wherein the copper pipe (121, 141) comprises: a plurality of straight tubes extending along the arranged direction of the plurality of fins (122, 142); and a plurality of return bends connected to one end of one of the plurality of straight tubes and one end of another one of the plurality of straight tubes by welding, wherein burrs having a circumference greater than an outer diameter of each straight tube are formed at both ends of the plurality of straight tubes due to expansion of the tubes, characterized in that: a distance between a rim of the burr and an outer surface of the straight tube is 0.4 mm to 1.8 mm, and coating layers providing corrosion resistance are formed on surfaces of the plurality of return bends, surfaces of the weld zones formed at both ends of each return bend, and surfaces of the burrs. a cabinet forming an outer appearance; a drum provided inside the cabinet to accommodate clothes therein; and a heat exchanger (120, 140, 1312) to remove moisture from the clothes accommodated in the drum or to generate hot air, wherein the heat exchanger (120, 140, 1312) comprises: a copper pipe (121, 141) forming a refrigerant circulation passage; and a plurality of fins (122, 142) arranged at positions spaced apart from each other along one direction, and coupled to an outer circumferential surface of the copper pipe (121, 141), wherein the copper pipe (121, 141) comprises: a plurality of straight tubes extending along the arranged direction of the plurality of fins (122, 142); and a plurality of return bends connected to one end of one of the plurality of straight tubes and one end of another one of the plurality of straight tubes by welding, wherein burrs having a circumference greater than an outer diameter of each straight tube are formed at both ends of the plurality of straight tubes due to expansion of the tubes, characterized in that: a distance between a rim of the burr and an outer surface of the straight tube is 0.4 mm to 1.8 mm, and coating layers providing corrosion resistance are formed on surfaces of the plurality of return bends, surfaces of the weld zones formed at both ends of each return bend, and surfaces of the burrs. a copper pipe (121, 141) forming a refrigerant circulation passage; and a plurality of fins (122, 142) arranged at positions spaced apart from each other along one direction, and coupled to an outer circumferential surface of the copper pipe (121, 141), wherein the copper pipe (121, 141) comprises: a plurality of straight tubes extending along the arranged direction of the plurality of fins (122, 142); and a plurality of return bends connected to one end of one of the plurality of straight tubes and one end of another one of the plurality of straight tubes by welding, wherein burrs having a circumference greater than an outer diameter of each straight tube are formed at both ends of the plurality of straight tubes due to expansion of the tubes, characterized in that: a distance between a rim of the burr and an outer surface of the straight tube is 0.4 mm to 1.8 mm, and coating layers providing corrosion resistance are formed on surfaces of the plurality of return bends, surfaces of the weld zones formed at both ends of each return bend, and surfaces of the burrs. a plurality of straight tubes extending along the arranged direction of the plurality of fins (122, 142); and a plurality of return bends connected to one end of one of the plurality of straight tubes and one end of another one of the plurality of straight tubes by welding, wherein burrs having a circumference greater than an outer diameter of each straight tube are formed at both ends of the plurality of straight tubes due to expansion of the tubes, characterized in that: a distance between a rim of the burr and an outer surface of the straight tube is 0.4 mm to 1.8 mm, and coating layers providing corrosion resistance are formed on surfaces of the plurality of return bends, surfaces of the weld zones formed at both ends of each return bend, and surfaces of the burrs. a distance between a rim of the burr and an outer surface of the straight tube is 0.4 mm to 1.8 mm, and coating layers providing corrosion resistance are formed on surfaces of the plurality of return bends, surfaces of the weld zones formed at both ends of each return bend, and surfaces of the burrs.