An optical probe that has an end having a reduced diameter is provided. An optical probe has a proximal end to be connected to a measurement unit of an OCT device and a distal end from which observation light exits and includes an optical fiber, an optical connector that is connected to the OCT device, a Grin lens corresponding to a light collection optical system and a light deflection optical system that are optically connected to the optical fiber at the distal end, a needle that rotatably accommodates the optical fiber and the Grin lens, a handpiece that rotatably accommodates a part of the optical fiber between the proximal end and the distal end and that holds the needle, and a support tube that is secured to the optical connector on a proximal end side and that is rotatably accommodated in the handpiece on a distal end side. An outer diameter of the needle is less than an outer diameter of the support tube.
