Silicone rubber insulation materials, with their advantages of weather resistance, water repellency, light weight, and low cost, are widely used in composite insulators in power systems. However, as the number and duration of composite insulator operations increase, and under the long-term exposure to electric fields, mechanical loads, and complex and variable environmental factors, the aging issue of silicone rubber sheds has become increasingly prominent, posing a threat to the safe and stable operation of the power grid. This paper comprehensively reviews the aging characteristics and mechanisms of high-temperature vulcanized silicone rubber materials under the influence of corona discharge, ozone, ultraviolet radiation, acid and alkali, high temperature, surface arcing, and multiple factors simultaneously. Furthermore, various models for predicting the lifespan of these materials are analyzed. Finally, the paper provides an outlook on the aging and lifespan prediction of composite insulators.