Because of the excellent hydrophobicity and hydrophobicity migration, silicone rubber composite insulators have an out-standing anti-pollution flashover performance, so they are often selected as the first choice to deal with pollution flashover accidents. However, in some special industrial dust areas, creepage and electric erosion occurs on the surface of composite insulators after short-term operation, which eventually develops into insulation failure. In order to study the corrosion failure process of composite insulators operated in special industrial dust areas, the samples of composite insulators from a special industrial park are taken, and the pollution degree and pollution composition, pollution flashover voltage gradient, hydrophobicity, and microscopic properties of samples are tested. Furthermore, the failure process of the insulators is analyzed. The results show that the equivalent salt deposit density (ESDD) of insulators is about 0.1~0.2 mg/cm², and the pollution composition is similar to that in chemical industry pollution area. With natural pollution on the surface, the hydrophobicity of the insulators is great, but the hydrophobicity loss, recovery, and migration properties cannot meet the operation requirements. The cause of insulation failure is the decrease of hydrophobicity caused by corona discharge. The decrease of hydrophobicity leads to electric erosion of the umbrella skirts, and finally develops into insulation failure.