Two major concerns in using polymer composites for load bearing structural applications are time dependent degradation in modulus and strength, measured by creep and creep rupture tests. Previous studies on creep of polymer composites focused on the individual and interactive effect of one or more of factors such as Stress-Temperature, Stress-Temperature-Physical Aging and Stress-Temperature-Moisture. While the effect of stress, temperature, and moisture on creep rupture is well documented, limited studies have focussed on the effect physical aging on creep rupture of polymer composites. No effort has so far been made to study the combined effect of the above factors on creep and creep rupture of polymer composites. Hence, the present investigation was undertaken to experimentally study the individual and interactive effect of temperature, stress, physical aging, and moisture on creep (linear and non-linear region), creep rupture and fracture of a thermoset epoxy resin (F263) and its composite (Hexcel Corporation's F263 epoxy resin reinforced with T 300 carbon fibers). (Abstract shortened by UMI.)