The invention discloses a method for measuring blue light weighted radiance spatial distribution, which comprises the following steps of measuring a light distribution curve of a light source, the size of a luminous surface, the radiance of the light source and a light source spectrum under a typical irradiation distance, and calculating by adopting a blue light weighted radiance spatial distribution fitting algorithm to obtain a blue light weighted radiance spatial distribution table. According to the method, the spatial distribution condition of blue light hazards is measured and calculated,and the spatial distribution condition of blue light hazards in a light source application scene, namely the magnitude of blue light weighted radiance at any position in the space can be calculated.