A measuring probe (40, 41, 42, 43, 44) comprising: an objective optical system (11, 114) for receiving a light beam from a measuring object, an interference filter (13A, 14A, 15A; 134A) having a predetermined transmittance characteristic, a light receiving sensor (13B, 14B, 15B; 134B), and a single fiber (13C, 14C, 15C; 134C) which is interposed between the objective optical system and the interference filter, the single fiber being constituted by a single fiber strand, wherein the measuring probe is configured in such a manner that the light beam is allowed to be transmitted through the interference filter (13A, 14A, 15A; 134A), and then is allowed to be incident onto the light receiving sensor (13B, 14B, 15B; 134B) for obtaining an intensity of the light beam, wherein the light beam is output from an exit face of the single fiber (13C, 14C, 15C; 134C) with a predetermined luminous intensity distribution and in a uniformized state regardless of position information or angle information about the measuring object, the light beam is incident on the interference filter (13A, 14A, 15A; 134A) with a predetermined luminous intensity distribution as a function of incident angle in a range of incident angles, the divergence of the light beam incident onto the interference filter is set to 15 degrees or more with respect to a normal line to the interference filter, and the predetermined transmittance characteristic of the interference filter (13A, 14A, 15A; 134A) is set by taking into account the predetermined luminous intensity distribution as a function of incident angle of the light beam incident on the interference filter, such that the light-receiving sensitivity of the measuring probe at the light receiving sensor approximates a desired color matching function (13B, 14B, 15B; 134B). an objective optical system (11, 114) for receiving a light beam from a measuring object, an interference filter (13A, 14A, 15A; 134A) having a predetermined transmittance characteristic, a light receiving sensor (13B, 14B, 15B; 134B), and a single fiber (13C, 14C, 15C; 134C) which is interposed between the objective optical system and the interference filter, the single fiber being constituted by a single fiber strand, wherein the measuring probe is configured in such a manner that the light beam is allowed to be transmitted through the interference filter (13A, 14A, 15A; 134A), and then is allowed to be incident onto the light receiving sensor (13B, 14B, 15B; 134B) for obtaining an intensity of the light beam, wherein the light beam is output from an exit face of the single fiber (13C, 14C, 15C; 134C) with a predetermined luminous intensity distribution and in a uniformized state regardless of position information or angle information about the measuring object, the light beam is incident on the interference filter (13A, 14A, 15A; 134A) with a predetermined luminous intensity distribution as a function of incident angle in a range of incident angles, the divergence of the light beam incident onto the interference filter is set to 15 degrees or more with respect to a normal line to the interference filter, and the predetermined transmittance characteristic of the interference filter (13A, 14A, 15A; 134A) is set by taking into account the predetermined luminous intensity distribution as a function of incident angle of the light beam incident on the interference filter, such that the light-receiving sensitivity of the measuring probe at the light receiving sensor approximates a desired color matching function (13B, 14B, 15B; 134B).