A grille shutter apparatus arranged at a grille opening portion at a frontal portion of a vehicle body includes a frame shaping a flow path of air flowing into the vehicle body from the grille opening portion, a movable fin rotationally supported by the frame and configured to control a flow amount of the air by providing an opening movement and a closing movement, the movable fin including a fin portion and rotary shafts rotationally supported by the frame, the rotary shafts including exposure portions configured to be arranged on the flow path of the air, at least one first shielding wall extending radially outward of the rotary shaft and provided at the exposure portion and a second shielding wall arranged at an upstream side of the air that flows in relative to the exposure portion extending in a direction intersecting a direction of the air that flows in.