Methyl violet was combined with graphene modified electrode by electrochemical method to prepare the poly( methyl violet)-graphene modified electrode. The electrochemical behavior of phoxim on the modified electrode was studied. The reduction peak current versus the concentration of phoxim showed a linear relation over the range of 8. 0 × 10- 8~ 2. 0 × 10- 5mol / L. The detection limit was 4. 0 × 10- 8mol / L. The method has been successfully applied for the determination of phoxim in real food with satisfactory results.