Abstract: High altitude and low temperature will have a significant impact on type selection and layout of 1 000 kV substation equipment. At present, there are no design and construction experiences as well as related technical reserves for UHV substations under such ambient conditions. Based on an investigation of the current equipment manufacturing level and the operation conditions of existing projects in such environment, and after a comparison of different technical schemes, the paper proposes the external insulation correction method for 1 000 kV equipment, the type of 1 000 kV equipment bushing and the installing principle of heating belt for GIS under the ambient temperature of –45℃ and below the altitude of 3 500 m. The recommended equipment layout scheme is presented through technical and economic comparison. The research results can provide a reference for construction of the follow-up 1 000 kV substations.