An oral interface apparatus with negative pressure is provided in the present invention for improving the comfort of soft tissue in oral cavity and increasing fixation of the oral interface. The oral interface apparatus is elastic and can fit variable shape or size of oral cavity. The oral interface is also easy to put on and take off, thus the convenience and safety of usage is both enhanced. In another embodiment, a method for maintaining oral negative pressure and collecting saliva by coupling the oral interface apparatus to a liquid collecting apparatus for effectively providing negative pressure to the oral cavity and sucking the saliva to an absorber disposed therein so as to prevent leakage or contamination.本發明提供一種負壓式口腔介面裝置其係可減少負壓介面對口腔內軟組織造成的不適感以及增加固定性,減少嘴巴的漏氣造成鬆脫。此外,該口腔介面裝置體積較小且具有彈性,因此適用不同口腔尺寸與形狀,使用中易於裝上與脫下,提高使用者的方便性與安全性。在另一實施例中,本發明更提供一維持口腔負壓與收集液體之方法,其係將該口腔介面裝置與一集液裝置相連接,該集液裝置可以有效的提供口腔內負壓以將該口腔介面裝置內之液體吸出而收集至集液裝置內之吸取元件以避免口水外漏或造成污染。2‧‧‧口腔介面裝置20‧‧‧第一夾持部201‧‧‧第一構件202‧‧‧第二構件203‧‧‧第一容置空間21‧‧‧第三構件213‧‧‧溝槽22‧‧‧第二容置空間23‧‧‧流道
