The objective of this study was to know the influence of soft denture liners on raising the masticatory efficiency when it is added to base of complete dentures This study included ٢٥ patients ٣ groups . When patients used complete dentures with soft denture liner, masticatory efficiency increased by ١١,٢٥٪ , there was gradual healing (recovery ) of mucous membrane, and the patients needed shorter time (٦-١٠ days) to accept their complete dentures .