The invention discloses a noise-reduction and damping system for a track in a tunnel. The noise-reduction and damping system comprises a damping unit, wherein the damping unit is arranged below the track and is connected with the track through a fixing unit; the damping unit comprises a top plate, a base, a first damping part and a second damping part; the top plate is fixedly connected with the fixing unit; the base is connected with the top plate through a supporting unit; the supporting unit has a hollow structure; the first damping part is arranged in the supporting unit; and the second damping part is arranged between the top plate and the supporting unit. The noise-reduction and damping system for the track in the tunnel has the advantages that the damper is positioned between the track and the ground, vibration transmitted from the track to the ground is relieved, and is weakened, the damping and noise-reduction effects are excellent, and by arrangement of the damping parts, thedamping and noise-reduction effects are further improved.