The invention discloses a model of simulating surface discharge of a basin-type insulator in an entity GIS. The model of simulating surface discharge of a basin-type insulator in an entity GIS includes a high-tension bushing, a metal can body, an inner conductor, an outer conductor, an insulator, a surface foreign matter, a ground wire, an insulation pedestal and a grounding body, wherein the high-tension bushing is arranged at the top of the metal can body; the bottom of the metal can body is provided with the insulation pedestal; the insulation pedestal is tube-shaped, and the upper end of the insulation pedestal is provided with a ring-like groove; the lower part of the tube-shaped outer conductor is embedded in the ring-like groove; the outer conductor is divided into upper and lower parts, and the insulator is arranged at the middle part of the outer conductor; the upper and lower parts of the outer conductor are fixed through a plurality of fastening screws which are distributed uniformly, and the insulator is fixed at the middle part; the inner conductor, the outer conductor and the insulator are assembled into one body to form a coaxial cylinder structure; the replaceable surface foreign matter is arranged on the insulator; and one end of the ground wire is connected with the fastening screws, and the other end of the ground wire is connected with the can body through the internal thread, and the bottom of the can body is connected with the grounding body. The model of simulating surface discharge of a basin-type insulator in an entity GIS can simulate discharge caused by the surface foreign matter of the basin-type insulator in the entity GIS, has clear and typical discharge characteristics, and is in good agreement with engineering practically.