A method of mounting an electronic door lock on a door includes: a manual operation to rotate a protrusion of a rotational actuator to initially press a switch; and an operating procedure implemented by the electronic lock for determining a correct mounting direction of the electronic door lock. The operating procedure includes controlling, in response to a signal sent by the switch that is initially pressed, a driving unit to rotate the protrusion in a direction from the initially pressed switch to the other initially un-pressed switch and to drive a latch to move from an unlatched position toward a latched position, followed by stopping and subsequently controlling the driving unit to rotate the protrusion in a reverse direction and to drive the latch to move toward the unlatched position.