To provide a heat transfer pipe for a falling liquid film type evaporator having good refrigerant wetting and spreading performance on the outer face and allowing the formation of a thin liquid film while suppressing dry-out.

The heat transfer pipe 1 comprises a pipe body 2 formed of copper and a plurality of square truncated cone shaped protrusions 3 spirally arranged on the outer face of the pipe body 2. An angle θ1 between the pipe peripheral direction of the pipe outer face and the arranging direction of the protrusion 3 is 0-19°. In the cross section including the pipe axis, the minimum width of a groove portion 4a is not smaller than the width of the base of the protrusion 3, and in a pipe axis perpendicular cross section, an angle between both side faces of the groove portion 4b is 15-50° and the minimum width of the groove portion 4b is 0.10-0.30 mm. A spiral rib 5 is formed on the inner face of the pipe, and the twisting angle of the rib 5 to the pipe axial direction is 38-47° and the height of the rib 5 is 0.20-0.35 mm.