A brushless motor for a blower fan unit is comprised of a heat sink which has a heat radiating portion and a pair of supporting legs extending from both opposite sides of the heat radiating portion. A free end portion of each supporting leg is in contact with an electric circuit board. A pressing member has a pressing portion, a pair of positioning portions perpendicularly extending from opposite end portions of the pressing portion, and a pair of connecting portions projecting from the pair of positioning portions respectively. The connecting portions are engaged with supporting legs of the heat sink respectively. The pressing portion presses switching devices to the heat sink. The positioning portions are inserted into the through-holes of the electric circuit board respectively.