Selective Laser Sintering (SLS) is an accepted and improving technique for additive manufacturing in many different areas, from the applications of aerospace to automotive, consumer products to dental and medical materials. Lightweighting is a significant issue, especially in terms of the automotive and aerospace industries, mainly to increase fuel efficiency and reduce CO(2)emission. The density reduction can be obtained by the addition of Hollow Glass Microspheres (HGMs) to Polyamide 12 (PA 12) polymer matrix. This study covers the different amounts of HGM filled PA 12 productions by SLS method and final structure characterization of PA 12-HGM composites. According to the performing thermal, physical, and mechanical tests, on increasing the amount of HGM in the structure, 10, 15, 20 weight percentages, respectively, the density of composites has been reduced significantly up to 20% for 20% of HGM filled PA 12 (PA 12-20HGM) composite, besides having a substantial rise in E-modulus.