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Dipole and quadrupole surface plasmon polariton (LSPP) resonances of gold nanoparticle array were directly investigated by a near-field scanning optical microscope (NSOM) in the fiber-collection mode. Separated gold nanoparticles on the quartz substrate were fabricated by nanosphere lithography. Results demonstrate that controlling the incident polarization and angle of oblique incidence enables to excite dipolar and quadrupolar LSPP at 633- and 488-nm excitations. This observation facilitates the understanding of LSPP and interactions with nanostructures in the near field that can be used as a guideline for fabricating nanostructures in controlling spatial distributions of LSPP for ultra sensitive bio-/chemo-detectors or plasmonic metamaterials.