A gun suppressor having a single or multiple vacuum chambers that create a vacuum enclosed volume for gases to expand into. Accordingly, the pressure of the gas that exits the suppressor is reduced significantly; therefore, the sound of the gun firing is more silent than conventional silencers. Prior to firing the gun, a vacuum seal is placed at the exit orifice of the suppressor and a vacuum is created inside of the suppressor with the use of a vacuum pump. The vacuum chamber reduces the pressure wave caused at the end of the firearm's barrel. When the firearm is discharged, the gases fill the vacuum chamber instead of exiting at normal atmospheric pressure level. As the bullet continues its travel through the end of the suppressor, it perforates the vacuum seal and continues its flight path.