At recent decades, polymer composite materials become more widespread and developed in critical areas of engineering practice. They are used, in particular, in aircraft, rocket engineering, shipbuilding, railway transport and construction. Advantages of these materials are high strength and stiffness, lightness, high fatigue strength, chemical inertness, heat and electrical conductivity, and others. Because these materials are used in critical areas of engineering practice, so this makes their long-term aging and creep characteristics of paramount importance. At the same time, the physical and chemical characteristics of these materials essentially changed after long-term operation, significantly due to the aging process. Thus, investigations of aging of these materials are much needed. Experimental studies on alternation of natural and thermal aging and deformation aging were conducted to study the evolution of creep characteristics of carbon fiber reinforced plastics (CFRP). The experimental creep curves after different aging programs were received. In total experiments were carried out during 3 years. It is shown, that the aging process has non-monotonic character, which should be considered in engineering practice at design of structural elements made of polymer composite materials.