Composite insulators are important insulation equipment for transmission lines

so their aging problem is concerned by the relevant departments and scholars.In order to study the effect of different environmental factors on the aging of composite insulator

in this paper

composite insulators from four typical areas are chosen to do ther mal stimulation current（TSC）test

Fourier Transform Infra-Red（FTIR）spectrum test and Scanning Electron Microscopy（SEM）test

and the differences of the composite insulators from different areas are compared.The results show that there are some differences in the microscopic characteristics of samples from different areas.The aging degree of the samples from Zhejiang is higher than that from other areas

which may be related to the salt spray and wet environment.The aging degree of the samples from Qinghai is relatively mild.The aging degree of the samples from Heilongjiang is between the former two areas.The damage degree of surface and functional groups of samples from Henan is higher

but their charge amounts are relatively small.The results are helpful to consider the influence of environmental factors on the running composite insulators

which can provide reference for operation and maintenance.