A linear guideway with damping is provided mainly comprising a guide rail and a slider module, said slider module comprising a slider body, a plurality of roller balls, caps for roller balls to circulate and a damping block. The slider module is provided with said damping block inside to damp said linear guideway without adding extra components to reduce vibration. Furthermore, a Damping adjustment device is provided to adjust a damping effect formed by contacting said damping block with said slider body and said guide rail in order to provide optimal vibration absorption.