Thr ARIES-I tokamak is a conceptual reactor drsigii based on advanced technology and modest extrapolation from the present clay physics database. The ARIES-I blanket ntilizes SiC'/SiC' composite materials as structural material with lieliiini gas as the coolant. Until recently the brittle failure behavior of monolithic ceramic materials has posed a i~rohlem for rising ceramics as structural materials. Recent development s in nia~iiifact uring and processing of fiber-reinforced rerainics make Si<'/Sic' composites a promising candidate for future power plants. Silicon carbide composites are advantageous from a safety and waste disposal stand point because of the low activation and their very low decay after-heat respect ively. The tlienno~~iechanical properties and neutron irradiation response of SiC/SiC composite materials are reviewed. Composite design eqciations are used to approximate a window of allowable design stresses for the first wall and blanket strnctiire of the ARIES-I tokamak reactor. The ANSYS finite eleiiient structural analysis code is used to analyse the thermal and mechanical hrliavior of the first wall under normal operating conditions. [t is roncluded that with minor extrapolations from todays manufacturing experience, SiC/SiC composites offer a viable striictitral material choice thus improving the safety and environmental aspects of future fusion power plants compared with coal or imclear.