The present invention provides a scanning method to reduce overhead in a millimeter wave (mmWave) scanning scheme by using position information of a terminal in a mmWave system, and devices supporting same. The method for the terminal performing mmWave beam scanning based on position information mmWave beam scanning based on position information of the terminal in the wireless access system supporting millimeter wave (mmWave) technology, according to one embodiment of the present invention, comprises the steps of: receiving, from a legacy base station, a position reference signal; calculating measurement information to calculate the position information of the terminal based on the positioning reference signal; transmitting the measurement information to the legacy base station; receiving, from a mmWave base station, first angle information generated based on the measurement information; determining a mmWave pCell by performing a first mmWave beam scanning based on the first angle information; and transmitting, to the mmWave pCell, a mmWave pilot signal for a second mmWave beam scanning.