To provide an electric steering position adjustment device strengthening an anti-theft property at low cost.

An immobilizer 200 has a data to be coded operation part 202 for producing data to be coded from vehicle key information and random number data; and a code operation part 203 for producing the data to be coded by applying predetermined operation to the produced data to be coded, and a tilt/telescopic device 1 is provided with a code operation part 130 for producing the coded data using the same operation as the operation while making the data to be coded input from the immobilizer 200 as input; a comparison part 131 for comparing the coded data produced in the code operation part 130 with the coded data input from the immobilizer 200; and a control part 132 for allowing execution of steering position adjustment control when the comparison result is coincident and forcedly controlling a position of the steering wheel such that steering is difficult when the comparison result is not coincident.