Abstract: Unsaturated polyester(UP) resin and ramie cloth were used to form composites by hand lay-up. Physical and mechanical properties, such as density, curing shrinkage, expansion after absorbing water, flexural strength, flexural modulus, impact strength and thermal stability, were studied and compared with those of UP resin casting. The results showed that the composites had greater densities, smaller curing shrinkages, less expansion after immersing in the distilled water. It was improved mechanical properties than UP resin casting. The composites also had more thermal stable than pure UP resin casting.