Abstract: It was found at the scene that the silicone grease applied at the interface between cross-linked polyethylene and silicone rubber in the cable accessories would dry out, ultimately causing the accessories to fail. The key reason for drying is that the silicone rubber absorbs the silicone grease. In order to clarify the compatibility between cable accessories silicone rubber and silicone grease, as well as the influence of swelling on the performance of silicone rubber, this paper first analyzes the absorption characteristics of the silicone rubber for the silicone grease from the perspectives of the structure properties of the silicone grease, temperature, direct current electric field, and the extension strain of the silicone rubber. Then this paper uses modern material analysis methods to study the effect of silicone grease absorption process on the properties of silicone rubber. The coefficient P is defined as a characteristic parameter of the comprehensive properties of the insulating silicone grease, which is determined by the molecular weight of the silicone oil, the size of the polarity, and the oil content of the silicone grease. The results show that choosing a silicone grease with a smaller coefficient P can slow down the swelling effect to silicone rubber, while high temperature, positive direct-current electric field, and high extension strain of the silicone rubber will aggravate the swelling phenomenon. Finally, the crosslinking density, activation energy, volume resistivity, dielectric properties and breakdown strength of silicone rubber are reduced to a certain extent, and the surface potential and trap characteristics of the material are also affected.