A kind of functional polysiloxane oligomer (FPSO) was employed to mix with silicon dioxide (SiO₂), aluminium hydroxide (ATH) and magnesium hydroxide (MH) for modifying the inorganic particles, and then the modified inorganic compound (MIC) was introduced into ethylene-vinyl acetate copolymer (EVA) via melt blending, then the EVA cable materials containing 50% MIC modified with different dosages of FPSO were prepared. The structure and properties of the materials were studied by SEM, DSC, rotational rheometer, electronic universal testing machine, etc. SEM images show that the presence of FPSO promotes the dispersion and compatibility of MIC in EVA matrix and a compact and stable residual char is formed from the combustion of EVA cable materials. DSC curves show that the crystallinity of EVA is enhanced since the lower dosages of FPSO is introduced into EVA composites, hence mechanical properties of which are improved. The rheological testing reveals there is an obvious reduction of storage modulus and loss modulus due to the existence of FPSO, as a consequence of the better dispersion of MIC in EVA matrix and the strong interfacial adhesion between MIC and EVA. With only 0.48% FPSO loading, the EVA composites exhibit better mechanical, low smoke, halogen-free flame retardant and oil resistant performance, which would show promising prospects in harsh environment when used as cable materials.