Three-dimensional (3D) printed poly (ethylene glycol) diacrylate (PEGDA) objects have been reinforced with 1%, 3% and 5% silica (SiO2) nanoparticles. Rheological characterizations were conducted for each formulation and 3D-printed using a stereolithographic apparatus (SLA) 3D printer. The tensile and compressive properties of the as-printed nanocomposites were investigated and compared with unreinforced samples. Additionally, the mechanical properties of the objects before and after swelling the samples in deionized water were compared with as-printed ones. Adding SiO2 increased the tensile and compressive strengths of the 3D-printed PEGDA. The tensile and compressive strengths of swollen PEGDA/SiO2 nanocomposite specimens were generally higher than the unswollen specimens.