PURPOSE: To improve basic performance in a mixed flow fan and to abate a noise with a simple design by forming a triangular plate solidly in each front edge in a plurality of blades arranged in and around a hub part so as to be externally inserted in a direction of rotation form the front edge part as one body.

CONSTITUTION: A mixed flow fan has a truncated cone hub part 1 for receiving power out of the outside and plural blades 2 attached to a peripheral part of this hub part 1. Projection from to a plan of a blade front edge 3 is formed rectilinearly. In this structure aforesaid, a triangular plate 5 with the same thickness as thickness of the blade 2 is solidly formed in the front blade front edge 3 so as to be externally inserted in a direction of rotation from the front edge. A side (a) of the plate 5 is made to go along an outer diametral circumference of the fan, while the other side (b) is made to stick close to a spot nearer to the circumference of the blade front edge 3. Improvement in basic performance in the mixed flow fan and abatement in a noise both is thus attained.