A narrow-band plasmonic filter based on dual-section metal-insulator-metal (MIM) structure is proposed, which consists of two metal layers and two insulator layer sections separated by a metal film. Each layer section contains four insulator periodic units structured by alternately stacking two insulators with different refractive indices. In the filter, both long range surface plasmons (LRSPs) and short range surface plasmons (SRSPs) at different resonant wavelengths are stimulated under the condition of light injection. Some transmission peaks are formed at a specific wavelength where the resonance condition for the LRSPs or SRSPs is satisfied. The insertion of a metal film into the two insulator layer sections enables us to increase the coupling distance of both ends of the metal film and to reduce the 3 dB bandwidth of transmission peak. At the same time, the resonance wavelength of LRSPs (SRSPs) will be blue-shifted (red-shifted), so that the transmission peaks of LRSPs and SRSPs overlap at a specific wavelength, resulting in the generation of a narrow-band transmission peak with high peak-to-notch contrast ratio. The transmission characteristics of the proposed filter are numerically investigated by using the finite-difference time-domain (FDTD) method. A transmission peak with a 3 dB bandwidth of 9.2 nm and a peak-to-notch contrast ratio about 37.2 dB is confirmed in the 1.3 μm range. By further increasing the width of metal film to 55 nm, the 3 dB bandwidth can be reduced to 7.2 nm and the peak-to-notch contrast ratio can be increased to 40.1 dB. Therefore, excellent narrow-band filtering performance is obtained.