An optical measurement method that can suppress variation in detection sensitivity even if an optical probe is bent, and an optical probe suitably used for the method are provided. An optical probe 10 includes an optical fiber 11 that transmits light between a proximal end 11a and a distal end 11b, an optical connector 12 connected with the optical fiber 11 at a side of the proximal end 11 a, a focusing optical system 13 and a deflecting optical system 14 optically connected with the optical fiber 11 at a side of the distal end 11b, and a support tube 15 and a jacket tube 16 surrounding the optical fiber 11 and extending along the optical fiber 11. The optical fiber 11 is twisted by a number of turns in a range from one turn/m to 50 turns per meter around an axis of the optical fiber as the center and fixed relative to the support tube 15.