A method for measuring the illumination values of fluorescent powder type LED light sources with different color temperatures in the environment of mesopic vision is disclosed. An illumination measuring instrument and a portable background luminance measuring instrument (4) or a portable reflectivity measuring instrument are used, and the illumination measuring instrument comprises an illuminometer probe (1) corrected by a photopic-vision spectral luminous efficiency function, a data processing unit (2) and a display unit (3). The method is characterized by comprising the following steps of: correcting the mesopic vision illumination values of the fluorescent powder type LED light sources with different color temperatures under different background luminance conditions L from 10-3 cd/m2 to 3 cd/m2 to obtain a group of correction factors B, and storing the correction factors B into an internal memory of the illuminometer; during measurement, firstly, measuring the photopic vision illumination values Ev, and then, measuring the actual background luminance value L of the road surface by using the portable background luminance measuring instrument; alternatively, measuring the reflectivity of the road surface by using the reflectivity measuring instrument, and acquiring the background luminance value L corresponding to the illumination of the road surface so as to obtain the corresponding correction factors B; and calculating according to the conversion equation of Emes=B*Ev between the mesopic vision illumination and the photopic vision illumination to obtain the corresponding mesopic vision illumination values Emes. The illuminometer for measuring the mesopic vision illumination values, which is obtained by the method of the invention, can accurately measure the illumination values in the mesopic vision environment and reflect the real mesopic vision illumination values of road lamps observed by human eyes.