The invention discloses a white LED light source generation device of a transmission type visibility meter. The white LED light source generation device comprises an LED light-emitting device (1), an optical splitter (4), a beam shaping device (5) and a light intensity detector (7). The input end of the LED light-emitting device (1) is electrically connected with a controller (8) through a signal generator (2). The optical splitter (4) is arranged on an output light path of the LED light-emitting device (1). The light intensity detector (7) is arranged on the output light path of the optical splitter (4), and the output end of the light intensity detector (7) is electrically connected with the controller (8). Particularly, the LED light-emitting device (1) emits white light, and the output light color temperature is 3000 K. The optical splitter (4) is an optical fiber optical splitter, wherein a first downlink optical interface (41) is located at a focus point of the beam shaping device (5), and a second downlink optical interface (42) is in optical connection with the light intensity detector (7). The output light path of the beam shaping device (5) is provided with a concave mirror (51), with the focal distance being 1200 mm, of an iris diaphragm (6), and the control end of the iris diaphragm (6) is electrically connected with the output end of the controller (8). The white LED light source generation device can serve as an ideal light source of the high-measuring-accuracy transmission type visibility meter.