A new type of metal-insulator-metal (MIM) surface plasmonic Bragg waveguide structure is proposed, in which one- dimensional Bragg grating is used as the intermediate insulating layer and the defect layer is introduced to construct the Bragg micro-cavity. The photon energy is well confined in the micro-cavity and most of the photon energy is localized along the interface between the insulating layer and metal. The structure parameters can be obtained through the analysis of the dispersion characteristics at the resonant wavelength of 1550 nm. The influences on the quality factor and mode volume by the structural parameters are analyzed by the finite-difference-time-domain (FDTD) method, such as the period number, the insulator layer thickness and the cavity length. The simulation results show that the performance of the cavity can be improved with proper parameters. The surface plasmonic Bragg nano micro-cavity has ultra-small mode volume V and high Q/V, which can achieve effective photon localization.