The utility model provides a tandem type axial fan. The tandem type axial fan is provided with a first axial fan, a second axial fan and a rectifying plate, the plurality of hollow through holes of the rectifying plate are separated by grid-shaped partition walls, penetrate in the axial direction, and are uniformly and two-dimensionally arranged to the outer edge part. An axial lower end portion of a first casing of the first axial fan is directly connected with an axial upper end portion of a second casing, and a rectifying plate is arranged at a connecting portion of the first casing and thesecond casing. The axial lower end portion of the first cylinder portion of the first housing faces the axial upper end portion of the second cylinder portion of the second housing with the flow regulating plate interposed therebetween in the axial direction. The axial end face of at least one of the axial lower end face of the first cylinder part and the axial upper end face of the second cylinder part is provided with a concave part which is concave towards the side opposite to the connecting part in the axial direction. A lead of at least one of the first axial fan and the second axial fanis housed in the recess. At least a portion of the recessed portion overlaps with a portion of the rectifying plate in the axial direction.