We propose a super resolution imaging technique called plasmonic structured illumination microscopy (PSIM), which combines the structured illumination microscopy technique with the tunable surface plasmon interference. Because of the high-resolution enabled by using surface plasmon interference as an illumination source, PSIM possesses higher image resolving power compared with conventional structured illumination microscopy. To demonstrate the technique, we present two specific types of plasmonic structure designs for PSIM. The final images from the simulations show 3-fold and 4-fold resolution improvement compared with conventional epi-fluorescence microscopy.