An evaporator, comprising: an evaporator case (110, 210, 310) having a box shape with both sides open,, the evaporator case (110, 210, 310) comprising two case sheets (111, 112, 211, 212, 311, 312) coupled in surface-contact with each other and bent to define the box shape; a cooling tube (120, 220, 320) formed by an empty space between the two case sheets (111, 112, 211, 212, 311, 312) to form a cooling passage for a flow of refrigerant; a heating tube (130, 230, 330) formed by an empty space between the two case sheets (111, 112, 211, 212, 311, 312) in a non-overlapping manner with the cooling tube (120, 220, 320); and a heating wire heater (140, 240, 340) inserted into the heating tube (130, 230, 330) to surround the evaporator case (110, 210, 310), and generating heat, in response to power supplied, such that heat for defrosting is transferred to the evaporator case (110, 210, 310), wherein the heating tube (130, 230, 330) comprises a first heating passage (130a, 230a, 330a) and a second heating passage (130b, 230b, 330b) disposed at both sides of the cooling tube (120, 220, 320), wherein the heating wire heater (140, 240, 340) comprises: a first part (140a, 240a, 340a) inserted into the first heating passage (130a, 230a, 330a); a second part (140b, 240b, 340b) inserted into the second heating passage (130b, 230b, 330b); characterized in that: the first heating passage (130a, 230a, 330a) and the second heating passage (130b, 230b, 330b) are each opened at both ends of the evaporator case (110, 210, 310), and that the heating wire heater (140, 240, 340) further comprises: a connection part (140c, 240c) connecting the first part (140a, 240a, 340a) and the second part (140b, 240b, 340b) to each other outside of the evaporator case (110, 210, 310). an evaporator case (110, 210, 310) having a box shape with both sides open,, the evaporator case (110, 210, 310) comprising two case sheets (111, 112, 211, 212, 311, 312) coupled in surface-contact with each other and bent to define the box shape; a cooling tube (120, 220, 320) formed by an empty space between the two case sheets (111, 112, 211, 212, 311, 312) to form a cooling passage for a flow of refrigerant; a heating tube (130, 230, 330) formed by an empty space between the two case sheets (111, 112, 211, 212, 311, 312) in a non-overlapping manner with the cooling tube (120, 220, 320); and a heating wire heater (140, 240, 340) inserted into the heating tube (130, 230, 330) to surround the evaporator case (110, 210, 310), and generating heat, in response to power supplied, such that heat for defrosting is transferred to the evaporator case (110, 210, 310), wherein the heating tube (130, 230, 330) comprises a first heating passage (130a, 230a, 330a) and a second heating passage (130b, 230b, 330b) disposed at both sides of the cooling tube (120, 220, 320), wherein the heating wire heater (140, 240, 340) comprises: a first part (140a, 240a, 340a) inserted into the first heating passage (130a, 230a, 330a); a second part (140b, 240b, 340b) inserted into the second heating passage (130b, 230b, 330b); characterized in that: the first heating passage (130a, 230a, 330a) and the second heating passage (130b, 230b, 330b) are each opened at both ends of the evaporator case (110, 210, 310), and that the heating wire heater (140, 240, 340) further comprises: a connection part (140c, 240c) connecting the first part (140a, 240a, 340a) and the second part (140b, 240b, 340b) to each other outside of the evaporator case (110, 210, 310). a first part (140a, 240a, 340a) inserted into the first heating passage (130a, 230a, 330a); a second part (140b, 240b, 340b) inserted into the second heating passage (130b, 230b, 330b); characterized in that: the first heating passage (130a, 230a, 330a) and the second heating passage (130b, 230b, 330b) are each opened at both ends of the evaporator case (110, 210, 310), and that the heating wire heater (140, 240, 340) further comprises: a connection part (140c, 240c) connecting the first part (140a, 240a, 340a) and the second part (140b, 240b, 340b) to each other outside of the evaporator case (110, 210, 310). the first heating passage (130a, 230a, 330a) and the second heating passage (130b, 230b, 330b) are each opened at both ends of the evaporator case (110, 210, 310), and that the heating wire heater (140, 240, 340) further comprises: a connection part (140c, 240c) connecting the first part (140a, 240a, 340a) and the second part (140b, 240b, 340b) to each other outside of the evaporator case (110, 210, 310).