An optoelectronic device and a method for assembling an optoelectronic device are provided which obviate the need for providing additional structural elements only for aligning purposes, thus reducing the costs and effort for manufacturing the optoelectronic device. An optoelectronic substrate is mounted on a mounting surface of a mounting substrate; a coupling region of the optoelectronic device faces a reflection element. A fiber endpiece is arranged at a mounting distance from the mounting surface, the mounting distance being larger than a distance of the coupling region from the mounting surface. The mounting surface is exposed and free of any further substrates, layers or structures for mechanically connecting or contacting the optical fiber. A fiber portion which is arranged at a distance from the fiber endpiece contacts a glue droplet arranged on or above the mounting surface of the mounting substrate.