A mixed binder containing liquid paraffin and silicone was blended with graphite powder to prepare a carbon paste electrode(CPE).Graphene/sodium dodecyl sulfate complex was used to modify carbon paste electrode to obtain a new modified carbon paste electrode(GR/SDS-CPE).Scanning electron microscopy and cyclic voltammetry were used to study the surface properties and electrochemical properties of the new modified carbon paste electrode，and the results showed that the specific surface area of GR/SDS-CPE was larger than that of CPE，so it is conducive to electron transfer.In pH 3.0 HAc-NaAc buffer solution，chloramphenicol(CAP) yields a sensitive oxidation peak with a potential of 0.194 V at the GR/SDS-CPE，and the oxidation peak current is 10 times larger than that at the CPE.Differential pulse stripping voltammetry(DPSV) showed that the oxidation peak current was linear with concentration of CAP in the range of 1.0×10-8-5.0×10-4 mol/L with a detection limit of 5.0 × 10-9 mol/L.With the advantages of simplicity，reproducibility and good selectivity，the method was applied in the determination of chloramphenicol eye drops and chloramphenicol residues in shrimp with satsfactory result.