Purpose: Saliva is a complex secretion that plays an important role in stomatognathic system activities, and its absence may lead to damaged functions such as mastication. Thus, the aim of this study was to investigate the effect of salivary flow rate on masticatory efficiency. Materials and Methods: Sixty dentate subjects were divided into three groups (n = 20) according to salivary flow rate: control (group 1), hyposalivation (group 2), and hypersalivation (group 3). All subjects from group 2 were under dermatologic treatment and taking systemic oral isotretinoin. Subjects from groups 1 and 3 were not taking any systemic medication and hypersalivation was induced in group 3 subjects by using a 6% citric acid solution. Masticatory efficiency was evaluated using an artificial test material (Optosil) and a sieving method. Masticatory efficiency was calculated as the weight percentage of the fragmented test food that passed through the 10-mesh (2-mm aperture) sieve. Data were analyzed using analysis of variance (P .05). Results: The masticatory efficiency values (%) under normal, hypo-, and hypersalivation were 6.40 (± 4.35), 7.63 (± 5.57), and 4.73 (± 4.85), respectively. However, no statistical differences were found among groups. Conclusion: Within the experimental design of this study, it could be concluded that patients with reduced or increased salivary flow do not present alterations in masticatory efficiency.