An evaporator manufacturing method includes providing cooling fins each formed with a pair of coolant tube accommodation parts, and expanding a first coolant tube and a second coolant tube after inserting the first coolant tube and the second coolant tube into the coolant tube accommodation parts of the plurality of cooling fins; providing a first jig and a second jig at different levels to bend the expanded first coolant tube and the expanded second coolant tube; bending the first coolant tube around the first jig alternately to form several horizontal parts spaced apart from each other along a vertical direction, and at the same time bending the second coolant tube around the second jig alternately to form several second horizontal parts spaced apart from each other along the vertical direction so that the second horizontal parts are positioned to the rear of spaces between the respective first horizontal parts; and connecting the first coolant tube and the second coolant tube. The coolant tube accommodation parts of each cooling fin are coupled to the first horizontal part and the second horizontal part, and inclined at an inclination angle to the vertical direction.