A mobile terminal, comprising: a terminal body having a front surface and a rear surface; a rear input unit comprising a first button portion externally exposed from the rear surface to receive a push input with a first function and a second button portion provided with keys (3254, 3255) disposed at both sides, respectively, around the first button portion to receive a push input with a second function different from the first function; a sensor disposed at a lower portion of the first button portion; and a flexible circuit board disposed at a lower portion of the first and the second button portion (325a, 325b), wherein the second button portion is provided with a through hole accommodating the first button portion to dispose the first button portion between the keys (3254, 3255), and the sensor is disposed to overlap with an inner region of the through hole, and at least a part thereof is formed to overlap with a first switch for activating the first button portion, wherein the flexible circuit board comprises: a sensor formation portion formed with the sensor; and a switch formation portion (340b, 340c) connected to the sensor formation portion and at least part of which is separated to vertically overlap with the sensor formation portion, and formed with the first switch and a second switch for activating the first and the second button portion (325a, 235b), respectively, wherein the sensor formation portion is extended and bent from a first switch formation portion of the switch formation portion (340b, 340c). a terminal body having a front surface and a rear surface; a rear input unit comprising a first button portion externally exposed from the rear surface to receive a push input with a first function and a second button portion provided with keys (3254, 3255) disposed at both sides, respectively, around the first button portion to receive a push input with a second function different from the first function; a sensor disposed at a lower portion of the first button portion; and a flexible circuit board disposed at a lower portion of the first and the second button portion (325a, 325b), wherein the second button portion is provided with a through hole accommodating the first button portion to dispose the first button portion between the keys (3254, 3255), and the sensor is disposed to overlap with an inner region of the through hole, and at least a part thereof is formed to overlap with a first switch for activating the first button portion, wherein the flexible circuit board comprises: a sensor formation portion formed with the sensor; and a switch formation portion (340b, 340c) connected to the sensor formation portion and at least part of which is separated to vertically overlap with the sensor formation portion, and formed with the first switch and a second switch for activating the first and the second button portion (325a, 235b), respectively, wherein the sensor formation portion is extended and bent from a first switch formation portion of the switch formation portion (340b, 340c). a sensor formation portion formed with the sensor; and a switch formation portion (340b, 340c) connected to the sensor formation portion and at least part of which is separated to vertically overlap with the sensor formation portion, and formed with the first switch and a second switch for activating the first and the second button portion (325a, 235b), respectively, wherein the sensor formation portion is extended and bent from a first switch formation portion of the switch formation portion (340b, 340c).