An optical object positioning apparatus including an optical element, a light sensor and a processing unit and a positioning method thereof are provided. The optical element includes a first surface and a second surface opposite to each other and perpendicular to a first axis, and has at least two light-passing regions. Light beams from an object to be positioned pass through the light-passing regions from the first surface to the second surface. The light sensor and the optical element are spaced by a predetermined distance on a direction of the first axis. The light sensor senses the light beams from the light-passing regions to generate at least two light-sensing signals. A distance between the object and the optical element is positively correlated to the predetermined distance. The processing unit receives the light-sensing signals and positions the object according to the light-sensing signals and the predetermined distance.