A coupling device (9) for an optical waveguide (8), in particular for an endoscope (2) or a light source (3), having an optical waveguide receptacle (11) aligned with a light-coupling optical unit (10), and having a centering device (12) for aligning an optical waveguide (8) with respect to the optical axis (26). The centering device (12) has at least two transmission elements (25) acted upon by a spring (30), and has centering elements (19), and wherein the spring force is distributed by a transmission element (25) uniformly to all the centering elements (19).