To provide a DC brushless motor which can be manufactured easily with a smaller number of part items and can be reduced in cost.

A stator 3 is supported on the outer surface of a boss 2. A rotary shaft 7 is rotatably passed through the boss 2 and supported there. A permanent magnet 10 facing opposite the stator 3 is supported on the rotary shaft 7 by a rotor 8 installed on the inner surface of a cylindrical part 9a of a rotor yoke 9. On the stator 3 side, a position detector 14 for detecting position in the turning direction of the rotor 8 is disposed facing opposite the permanent magnet 10 of the rotor yoke 9. A spacer 11 is supported by the stator 3 along the outer surface of the boss 2. A position detector installation board 19 is formed as an integral part of the spacer 11, in the direction crossing at right angles with the axis line of the boss 2. The position detector 14 is installed on the position detector installation board 19.