The invention relates to a wind collecting type wind power generating device. The wind power generating device comprises a base, a power generating unit, a wind collecting unit and a rotating unit, wherein the wind collecting unit comprises a plurality of wind collecting plates; two adjacent wind collecting plates define a wind collecting opening and a wind inlet of which the diameter is larger than the diameter of the wind collecting opening; the rotating unit is provided with a rotating shaft and a plurality of fan blades; each fan blade is provided with a fan blade body and a plurality of longitudinal sheet body parts arranged on the inner side surface of the fan blade body at intervals; two adjacent fan blades define a wind collecting space; and wind power led in from the wind inlet is gathered in the wind collecting space, so as to improve the fan blade pushing efficiency to increase the rotating speed of the rotating shaft, and further improve the power generating efficiency of the wind power generating device.