An object is to provide a silencing system that can achieve both high ventilation performance and high soundproof performance, can silence a plurality of pieces of resonant sound, and has high general-purpose properties since the silencing system does not need to be designed according to a tubular member. The silencing system includes one or more silencers that are disposed in a tubular member provided to penetrate a wall separating two spaces, and satisfies “0 0” in a case where a standardized effective modulus of elasticity in an interior space of the tubular member in which the silencers are disposed is denoted by Bn.