Strengthening concrete structure with E-glass fiber reinforced polymer (GFRP) is gaining more popularity, mainly due to their superior mechanical properties. However, there is insufficient information on environmental durability of glass fiber reinforced polymer, especially in harsh environmental conditions combined with sustained load. In this paper, the durability of an E-glass/ composite material under freeze-thaw cycle either in an unstressed state or loaded in about 30% of the initial ultimate load are investigated. The residual tensile properties of the GFRP are studied after coupled action of freeze-thaw cycle and sustained load. The results indicate that the single action of freeze-thaw cycle reduces the ultimate tensile strength and strain of the GFRP, and the coupled action of sustained load and freeze-thaw cycle further reduces the ultimate strength and strain of the GFRP.