A fan actuator device with an adjustable rotary angle having an upper connector rotated by a motor gear, a toggle mechanism formed by an upper connecting rod, a lower connecting rod and a coupling connector, a swinging arm connected to the coupling connector and a fan shelf and an adjusting handle. The upper and lower connecting rods are pivoted to an upper connector and the adjusting handle. Turning the adjusting handle changes the included angle between the upper and lower connecting rods, also changing the turning radius, to vary the swinging range of the fan.