Optical measurement methods are widely employed in both industrial and medical fields for two reasons: optical methods are non-invasive and have a high resolution. Among various optical methods, the method based on spectroscopy is actively applied in monitoring multiple factors from spectral information. Optical microscopes can overcome the disadvantages of these traditional methods to analyze nanoscale components, but they are flawed by diffraction limits that limit imaging resolutions to a few hundred nanometers. To overcome the shortage, post-processing techniques such as deconvolutions were employed, but there were also limitations. Meanwhile, several studies of optical profile inspection systems using confocal or patterned illuminations were also progressed by several research groups, resulting in measurements with improved resolutions. In this research, we investigated an ultrahighresolution optical inspection system for examining fabricated metallic nanostructures using structured illuminations. Images of nanoscale wires and posts reflected in the structured illumination formed by a Liquid-Crystal on Silicon (LCoS) spatial light modulator can be reconstructed to the ultrahighresolution image through post-processing, which shows the improvement of 200 in the lateral image resolution. Comparison with SEM, one of the typical nanostructure imaging instruments, confirms that the investigated system shows high performance and availability as a nanomaterials and nanostructures inspection platform. In particular, since it does not require special environmental conditions such as vacuum and can connect multiple systems into arrays, it saw hope that the optical inspection system can be employed as an inspection equipment for large nanoscale components.