Explosives detection for national and aviation security has been an area of concern for many years. In order to improve the security in risk areas, much effort has been focused on direct detection of explosive materials in vapor and bulk form. New techniques and highly sensitive detectors have been extensively investigated and developed to detect and identify residual traces that may indicate an individual's recent contact with explosive materials. This paper reports on the use and results of Surface Enhanced Raman Scattering (SERS) technique, to analyze residual traces of explosives in highly diluted solutions by using low-resolution Raman spectroscopy (LRRS). An evaluation of the detection sensitivity of this technique has been accomplished using samples of explosives such as Trinitrotoluene(TNT), Cyclotrimethylenetrinitramine (RDX) and HMX evaluated at different concentrations. Additionally, different SERS substrates have been studied in order to achieve the best enhancement of the Raman spectrum for residual amounts of materials. New substrates produced by gold-coated polystyrene nanospheres have been investigated. Two different sizes of polystyrene nanospheres, 625nm and 992nm, have been used to produce nanopatterns and nanocavities on the surface of a glass slide which has been coated with sputtered gold. Results from homemade substrates have been compared to a commercial gold-coated substrate consisting of an array of resonant cavities that gives the SERS effect. Sample concentration, starting from 1000ppm was gradually diluted to the smallest detectable amount. Raman spectrum was obtained using a portable spectrometer operating at a wavelength of 780nm.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.