A 3D-scanning optical imaging probe which inhibits rotation unevenness of rotational sections, shaft run-out, friction, and rotation transmission delay by reducing the occurrence of torque loss and rotation transmission delay, and which is capable of obtaining 3D scans and observation images within a fixed frontal range. A substantially tubular catheter has, provided along substantially the same line therein: a fixed-side optical fiber; a first optical path conversion means which is rotationally driven by a first motor, and which rotates and emits a beam of light forwards and tilted at an angle with respect to a rotational axis; and a second optical path conversion means which, at a tip side of a rotation-side optical fiber rotationally driven by a second motor, tilts an optical path by a micro-angle with respect to the rotational axis, and rotates and emits the beam of light to irradiate the first optical path conversion means therewith.