Aiming at controlling the running of Maglev (magnetically levitated) vehicles under snowfall, a measuring system for profiling snow depths in a U-shaped Maglev guideway by image processing was developed using the light cross section method. This system, composed of control and data analysis devices, a CCD-camera unit and a semiconductor laser scanning unit, measures the snow depth at 80 points in 2 minutes for every snow cover profile 4.6 min width. The field tests revealed that the system was capable of measuring the profiles with an accuracy of +/-10 mm except when the snow cover was saturated with water, irrespective of the measuring conditions such as the weather and the type of snow.