Denture liners are applied to the intaglio surface of dentures to achieve a more even force distribution, to reduce localized pressures and to have a cushioning effect between the denture and underlying denture bearing tissues. One of the most clinically challenging issues with these materials is hardening and debonding of soft liners from the denture base with time. The purpose of this study is to assess the effect of saliva and denture cleanser on the hardness and tensile bond strength of different denture liners. Hardness measurements of denture liners specimens will be done using Shore A Durometer and the tensile bond strength measurements of the specimens using Universal Testing Machine