A blade drive device includes: a board including an opening; a blade movable between a position receding from the opening and a position covering at least a portion of the opening; a first actuator including a first rotor rotatable about a first axis and a first stator, and being capable of driving the blade; a second actuator including a second rotor rotatable about a second axis and a second stator, and being capable of driving the blade; first and second positioning portions respectively positioning the first and second actuators; and a first biasing member respectively biasing the first and second actuators toward the first and second positioning portions.