Blower unit for vehicle

The present invention concerns a blower unit for a vehicle (1) comprising a casing (5), which defines an air passage (2), provided with an inside and an outside air introducing port (3,4); a damper (6), which opens or closes the inside or the outside air introducing port (3,4) ; and a blower (7) provided with a motor (71), a motor rotary shaft (71a) and a fan (72) rotatably driven by the motor (71), and the air passage (2) has a fan accommodating portion (23) which is provided on a leeward side of the damper (6), and accommodates the fan (72) of the blower (7). According to the invention, an inner surface of the casing (5) ranging from a portion of the casing near an end of a movable range of the damper (511a), to a portion of the casing near an end of the fan accommodating portion (23) on a windward side is formed in a flat surface or in a convex surface projecting toward the air passage (2).