The increasing need of fiber-reinforced polymer (FRP) in civil engineering applications gradually aroused serious concern of the long-term durability of this novel construction material. This study investigated the durability of concrete-filled FRP tube (CFFT) stubs, one of the recent applications of FRP composites for reinforcing concrete members, subjected to the combined freeze/thaw, heating/cooling, and wet/dry cycles with additional sustained axial load and continuous water immersion conditions. Mechanical and material characterization tests were conducted on the conditioned specimens to evaluate the degradation of mechanical properties and changes of physical, chemical and thermal properties. Test results showed that more degradation occurred on both strength and strain capacities of the CFFTs for wet environmental conditioning compared to the dry environmental conditioning. The sustained load further deteriorated the CFFTs in both strengths and strains slightly.