A sound-absorbing device is used for covering a mouth. The sound-absorbing device includes a cover body, a ventilation structure and a sound-absorbing portion. The cover body has a first chamber, a first and a second openings. The first chamber communicates with the first and the second openings. The first opening corresponds to the mouth. The ventilation structure is disposed at the second opening and has a second chamber, a third and a fourth openings. The second chamber communicates with the third and the fourth openings. The fourth opening is away from the first opening. The ventilation structure includes a plate disposed in the second chamber. The plate has a functioning surface facing the third opening. An edge of the plate and an inner wall of the ventilation structure has a gap in between. The sound-absorbing portion is located between the ventilation structure and the first opening.一種吸音裝置用以覆蓋嘴巴。吸音裝置包含罩體、通風結構與吸音部。罩體具有第一腔室與相對之第一開口與第二開口,第一腔室連通第一開口與第二開口,第一開口對應嘴巴。通風結構設置於第二開口,通風結構具有第二腔室與相對之第三開口與第四開口,第二腔室連通第三開口與第四開口,第三開口至少部分位於第一腔室內,第四開口遠離第一開口,通風結構包含至少一板體,設置於第二腔室內,板體具有作用表面,作用表面朝向第三開口,板體之邊緣與通風結構之內壁之間具有空隙。吸音部設置於通風結構與第一開口之間。100‧‧‧吸音裝置110‧‧‧罩體111‧‧‧第一腔室112‧‧‧第一開口113‧‧‧第二開口120‧‧‧通風結構120a、124b、160b‧‧‧內壁121‧‧‧第二腔室122‧‧‧第三開口123‧‧‧第四開口124‧‧‧板體125‧‧‧作用表面126‧‧‧邊緣127‧‧‧導管130‧‧‧吸音部131‧‧‧第一子吸音部132‧‧‧吸音面133‧‧‧第二子吸音部140‧‧‧布材150‧‧‧金屬箔160‧‧‧金屬片G‧‧‧空隙124a、160a‧‧‧穿孔
