An indoor device for an air conditioner is provided. The indoor device may include a heat exchanger mounting panel in which an orifice to pass air therethrough is formed, a centrifugal fan to inhale air in a shaft direction through the orifice and discharge the air in a radial direction, a motor to rotate the centrifugal fan, and a case to fix the motor and couple the motor to the panel. A first magnetic substance and a second magnetic substance that generate a repulsive force may be respectively disposed at a first surface opposite to the centrifugal fan in the panel and a second surface opposite to the panel in the centrifugal fan. In the first magnetic substance and the second magnetic substance, the same pole may be formed in a concentric circle and different poles may be alternately formed in a radial direction.