Recent developments in lightweight, dimensionally stable, portable telescopes have required the application of advanced materials. For example, composite telescopes with 0.4- and 1.4- meter primary mirrors are currently being developed for use at the Naval Prototype Optical Interferometer (NPOI). By fully utilizing composite construction for telescope elements such as optics, structure, mount, and end-fittings, the overall weight has been reduced nearly an order of magnitude over conventional designs. Furthermore, composite end-fittings reduce weight and increase stiffness at the secondary end of a telescope. Compared to their metallic counterparts, composite end-fittings contribute to reduced inertia, enhanced response, and improved performance. In this paper, details for the design and manufacturing procedure of a lightweight composite end-fitting for a telescope application are presented. The structural integrity of the end-fitting was verified by means of finite element analysis. It is shown that the use of composite materials provides significant weight savings over comparable end-fittings made of metal, in addition to a near zero coefficient of thermal expansion.