Aerospace electrical insulation materials are the boundaries of electrical signal transmission and effect for the deep space explorers. Evaluating the environmental adaptability of aerospace electrical insulation materials is need to be considered and optimized in the process of material selection，insulation design and process treatment. Starting with the environmental factors related to the electrical insulation properties of materials， this paper introduces the deep space radiation environment， thermal environment， gas environment and particle environment and their effects. Then the evaluation process， verification items and methods of deep space environmental adaptability are given， which provides a reference for the selection and evaluation of aerospace electrical insulation materials.