A navigation device with the auto mirroring function includes: a first driving route calculator configured to collect a current position and a destination of the vehicle and to calculate a first driving route corresponding to the current position and the destination by using previously stored map information; a mirroring determinator configured to determine whether mirroring is required based on a predetermined mirroring condition; a start signal transmitter configured to transmit a navigation application start signal to the mobile device when it is determined that the mirroring is required; and a mirroring controller configured to receive and mirror a second driving route transmitted from the mobile device.