PROBLEM TO BE SOLVED: To provide an endoscope system that forms an image having no image of a light spot on an object to be measured.SOLUTION: In the endoscope system 1, an endoscope includes: an imaging device 16 that forms an image signal of light by accumulating an electric charge in accordance with the light in a viewing field θ1 an electronic shutter that adjusts time for the imaging device to accumulate the electric charge a lighting unit 17 for emitting illumination light in the viewing field and an image processing part 25 that reads the image signal at a prescribed time interval and processes it to obtain an image. Further, in the system, a guide tube device includes: a range measuring part 48 that irradiates an irradiation position P1 on an object W to be measured that exists in the viewing field with position detecting light L1 and measures a distance to the irradiation position by detecting the position detecting light reflected at the irradiation position and a measuring condition control part 56 that controls the range measuring part. The measuring condition control part makes the range measuring part emit the position detecting light to detect the distance to the irradiation position on the object to be measured, when the imaging device does not accumulate an electric charge.
