An operation member 30 of an operation input device 20 includes a finger sensor 54 adapted to detect each of a plurality of fingers gripping the operation member 30. A controller 36 specifies the number of gripping fingers Ngf which is the number of fingers 300 gripping the operation member 30 based on the detection result of the finger sensor 54 and switches, in accordance with the number of gripping fingers Ngf, a type of an operation command corresponding to the operation input.