Objective To prepare polyaniline modified graphite (GO-g-PANI) through the in situ grafting reaction onto graphite surface. Methods Firstly the flake graphite was oxidized. Then amino group was introduced by reaction between hydroxy and silane coupling agent (KH550). The products were characterized by FTIR, SEM and resistivity tester and was used as conductive filler to prepare conductive coatings. Results The grafting yields were all over 92% under different proportions between aniline and graphite. When the weight ratio of graphite and aniline was 3∶1, needle polyaniline was formed on the graphite surface, and the resistivity value of the formed composite material reached the lowest value 12.8 Ω?mm. When the content of the modified graphite was 30%, the comprehensive performance of the coating was the best. Conclusion Polyaniline can graft onto graphite by the in situ reaction, and can improve the conductive properties of graphite oxide, and has potential applications in conductive materials and electromagnetic shielding materials.