An outer rotor type fan-motor comprising: a rotational shaft; a stator installed at an outer side of the rotational shaft; a permanent magnet assembly that covers an outer side of the stator at a certain distance and is installed at the rotational shaft; and a fan, at which the rotational shaft is fixed, that is rotated together with the rotational shaft and includes a hub that covers an outer side of the permanent magnet assembly and blades formed on an outer surface of the hub, wherein an inner surface of the hub and an outer surface of the permanent magnet assembly are separated, characterized in that a shaft fixing part is formed to be protruded from a central portion of the outer surface of the hub, the shaft fixing part having a rotational shaft insertion hole in which the rotational shaft is fixedly combined, wherein the permanent magnet assembly comprises: a cylindrical permanent magnet mounting part; and a disk-type shaft supporting part that covers one end of the permanent magnet mounting part, wherein the space between the outer surface of the shaft support part and the inner surface of the hub is smaller than the space between the outer surface of the permanent magnet mounting part and the inner surface of the hub, wherein a step (221 a) is formed at the inner surface of the shaft fixing part along a lengthwise direction of the rotational shaft, and wherein a step is formed at the inner surface of the hub along the circumference of the rotational shaft insertion hole (221 b). a rotational shaft; a stator installed at an outer side of the rotational shaft; a permanent magnet assembly that covers an outer side of the stator at a certain distance and is installed at the rotational shaft; and a fan, at which the rotational shaft is fixed, that is rotated together with the rotational shaft and includes a hub that covers an outer side of the permanent magnet assembly and blades formed on an outer surface of the hub, wherein an inner surface of the hub and an outer surface of the permanent magnet assembly are separated, characterized in that a shaft fixing part is formed to be protruded from a central portion of the outer surface of the hub, the shaft fixing part having a rotational shaft insertion hole in which the rotational shaft is fixedly combined, wherein the permanent magnet assembly comprises: a cylindrical permanent magnet mounting part; and a disk-type shaft supporting part that covers one end of the permanent magnet mounting part, wherein the space between the outer surface of the shaft support part and the inner surface of the hub is smaller than the space between the outer surface of the permanent magnet mounting part and the inner surface of the hub, wherein a step (221 a) is formed at the inner surface of the shaft fixing part along a lengthwise direction of the rotational shaft, and wherein a step is formed at the inner surface of the hub along the circumference of the rotational shaft insertion hole (221 b). a cylindrical permanent magnet mounting part; and a disk-type shaft supporting part that covers one end of the permanent magnet mounting part, wherein the space between the outer surface of the shaft support part and the inner surface of the hub is smaller than the space between the outer surface of the permanent magnet mounting part and the inner surface of the hub, wherein a step (221 a) is formed at the inner surface of the shaft fixing part along a lengthwise direction of the rotational shaft, and wherein a step is formed at the inner surface of the hub along the circumference of the rotational shaft insertion hole (221 b).