This research aimed to study the behavior and mechanisms of nitrile-butadiene rubber (NBR) in the accelerated aging air-circulating oven for different time periods. The appearance aging morphology was examined by using scanning electron microscope (SEM) to evaluate the surface of the rubber degradation and cross-link density was determined by swelling method. The evaluation of mechanical properties was measured by the tensile test. Functional groups at the surface of the rubber was analyzed with attenuated total reflection-flourier transform infrared spectroscopy (ATR-FTIR) and chemical composition The appearance aging morphology was examined by using scanning electron microscope (SEM) to evaluate the surface of the rubber degradation and cross-link density was determined by swelling method.