We demonstrate a dual-wavelength band optical frequency domain imaging (OFDI) system that provides high-resolution spectroscopic imaging with metallic nanoparticles as exogenous contrast agents. The local increase of the OFDI signal by elastic scattering from two different custom-fabricated nonspherical nanoparticles resonant at each wavelength band of the system was successfully detected, and we were able to distinguish and visualize the location of each of the nanoparticles in a scattering sample and in biological tissue.