The FKM-g-S_iR macromolecular compatibilizer was produced by using a high-temperature thermomechanical grafting process to graft long-chain vinyl silicone oils (S_iR, terminal vinyl dimethicone) with varying vinyl contents (0.09%,0.21%, and 0.63%) onto fluoroelastomer (FKM). The impact of initiator dosage, silicone oil dosage and vinyl content on the mechanical characteristics of FKM/MVQ (Methyl vinyl silicone rubber) blends was probed using a three-level orthogonal design experiment with a three-factor range analysis. Optimal conditions for the preparation of the compatibilizer were obtained accordingly. The findings indicated that the vulcanization properties, mechanical properties, and resistance to oil of the FKM/MVQ blends that were rendered compatible were optimized when the quantity of initiator Dicumyl Peroxide (DCP) was 0.25 parts, the volume of silicone oil was 9 parts, and the vinyl content was 0.63%. The composites exhibited the following specifications: the maximum torque difference can reach up to 12.56 dN.m, while the tensile strength and elongation at break can reach up to 8.39 MPa and 348.04%, respectively. Additionally, the rate of change in oil volume and mass can be reduced by 25.2% and 14.37%, correspondingly. The blended rubber's structure and performance were characterized using several methods, including Fourier transform infrared spectroscopy (FT-IR), Rubber processing analyzer (RPA), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Dynamic mechanical thermal analysis (DMTA). The results indicated that the compatibilizer significantly improved the compatibility of the FKM/MVQ blend.