A method and a system for controlling the opening/closing of a vehicle door are provided. The method includes determining whether a door is in a locked state and when the door is determined to be in the locked state, determining whether a smart key is within a predetermined distance. When the smart key is determined to be within the predetermined distance, a door latch module is changed to a “ready-to-open” state in the locked state of the door. The method further includes determining whether the smart key is maintained to be within the predetermined distance and operating an exterior handle of the door. When the exterior handle is operated, the door is opened and locking of the door is released simultaneously.