This paper studied the durability of Glass Fiber Reinforced Polymer (GFRP) Pole and Tower for power transmission under the UV and adverse temperature environment. The results show that both UV and adverse temperature environment influence the performance of GFRP material, with its strength significantly reduced, and its elastic modulus increased, while the Poisson's ratio changed slightly. Xenon lamp aging affects the material properties of the specimens with protective coatings more slightly than those without any protective coatings. High temperature environment affects the material properties of specimens more obviously than low temperature environment does. Therefore, when designing the GFRP Pole and Tower for power transmission exposed in UV and adverse temperature environment long-term, designers should consider the negative impacts of the external environment, and take appropriate protective treatments.