In this thesis, we report our theoretic investigation on the surface plasmon polaritons of noble metallic nanoparticles and its applications. By means of numerical experiments, we studied the general far-field and near-field optical properties of the promising hollow metallic nanoparticles, the pattern of far-field extinction efficiency and the near-field surface-enhanced Raman scattering. We demonstrated the distribution of plasmon resonance wavelength as functions of the geometrical factor of hollow spherical gold and silver nanostructures. In addition, we utilized a novel mechanism of harnessing the mechanical strain to controllably tailor the plasmon-based optical spectra of single metallic nanospheres and the array of metallic nanoparticle of spheres and circular discs. The second goal of this thesis is to utilize a novel mechanical-strain-induced effect to enhance the light-trapping performance of plasmonic solar cells. This multi-physical scheme has the potential of considerably reducing the thickness of semiconductor layer and hence save the cost of production of the solar cells. Corresponding simulation results demonstrated this strategy is promising to decrease the fabrication budget of solar industry.