SUMMARYObjective: The purpose of this in vitro studywas to compare the tensile strength betweentwo materials for the manufacture ofacrylic denture bases (Veracril® from NewStetic and SR Triplex Hot® from IvoclarVivadent), and to know the mechanicalproperties of materials to study that haveclinical implications.Methods: Laboratory tests were conductedunder the technical standard of ASTMInternational # D 638-03 to evaluate thetwo acrylic resin materials for denturebases, processed by pressed moulding. Theobservations were made using the universaltesting machine Tinius Olsen® brandH50KS to analyze the tensile propertiessuch as modulus of elasticity, elongation,yield strength, maximum strength, energy,effort and tensile stress between the twomaterials evaluated.Results: For the effort, maximum strengthand modulus of elasticity, high-impactacrylic resin SR Triplex Hot® showedhigher values. With regard to the characteristicsof maximum displacementbefore the fracture, elongation and energy,conventional acrylic resin showed highervalues. The only characteristic that showeda significant difference between the twogroups of thermo-cured acrylic resin wasthe modulus of elasticity where the highimpactacrylic resin obtained a much highervalue than conventional acrylic resin.Conclusions: The acrylic resin SR TriplexHot® presents higher values in some tensileproperties, while the Veracril® showsbetter in others. The only characteristic thatshowed a significant difference betweenthe two acrylic resins was the modulus ofelasticity.Keywords: Acrylic resin denture bases,tensile strength, high impact acrylic resin.