Provided are an optical measurement apparatus and an endoscope system which, when performing observation using an endoscope and measurement using a measurement probe of the optical measurement apparatus, can cancel an influence of observation light from the endoscope on the measurement by the measurement probe and also perform measurement accurately. The endoscope system 1 includes an endoscope light source device 5, a light receiving unit 322 for receiving light via the measurement probe 31, a computing unit 327a for measuring characteristics of a target object based on results of the light receiving by the light receiving unit 322, and a control unit 46 for switching a wavelength of the endoscope light source device 5 or of a light source unit 321 such that a wavelength of observation light emitted by the endoscope light source device 5 and a wavelength of measurement light emitted by the light source unit 321 are different from each other.
