Provided is an indoor unit for an air-conditioning apparatus including: a sensor box accommodating a sensor configured to detect light; a gearbox configured to hold the sensor box so as to be rotatable, and to be moved along a first axis together with the sensor box; a first motor configured to apply a force causing the sensor box to rotate; a second motor configured to apply a force causing the gearbox to move along the first axis; and a shaft inserted through the gearbox to be rotated by receiving the force from the first motor, in which, in the gearbox, the shaft is inserted, and the gear is accommodated so that a rotational force transmitted from the shaft is transmitted to the sensor box, the gear being movable along the first axis.