Composite material has been widely applied on space vehicle structures due to its light weight and designed stiffness modulus. Besides, some special mechanical properties that are always hardly changed in general metal materials, such as low CTE (coefficient of thermal expansion) and directional material stiffness, can be artificially adjusted to meet user’s requirements using composite material. For FORMOSAT-5 Remote Sensing Instrument (RSI) structure, space-qualified Carbon Fiber Reinforced Plastic (CFRP) composite material is largely applied because of its light weight and low CTE characteristics. RSI structure elements including primary mirror supporting plate, secondary mirror supporting ring and supporting frame are thus designed, manufactured and verified to meet specifications. In this paper, the structure manufacturing process, the detailed material properties and validation methods of these CFRP structure elements are introduced.