The chemical environment in the oral cavity significantly influences the structural degradation of tooth enamel, particularly in tribocorrosive conditions. This study explores the dual influence of citric acid on the wear and erosion behavior of human tooth enamel, focusing on the interaction between lubrication and corrosion effects. Reciprocating sliding tests were performed in citric acid solutions with different pH values and in distilled water. The coefficient of friction, depth of wear scar, static erosion depth, demineralization rate, total enamel loss, and subsurface nanohardness were evaluated. The results showed that citric acid solutions reduced the coefficient of friction compared with distilled water, with the lowest COF values observed at pH 6.2 and 7.0. Except for the pH 2.5 group, the depth of the wear scar in citric acid solutions was lower than that in distilled water, suggesting a citrate-related lubricating effect. However, under strongly acidic conditions, hydrogen ions promoted severe enamel demineralization and static erosion, resulting in hardness reduction and increased total enamel loss. A dynamic competition was observed between citrate-related lubrication and hydrogen ion-induced corrosion, with the balance between these processes determined by their relative concentrations. Higher citrate concentrations promoted faster adsorption and shorter running-in periods, enhancing lubrication, while stronger acidic conditions accelerated enamel dissolution. These findings contribute to a deeper understanding of the tribocorrosive processes affecting tooth enamel, offering valuable insights into the interplay between lubrication and corrosion in biological systems, with potential applications for the development of materials and strategies to mitigate wear and degradation in various biological and engineering contexts. Graphical Abstract