A dental mirror device comprises a holding unit and a mirror unit. The holding unit comprises a base, a handle and a driving module. The base has a surrounding wall, a partition wall and a fluid outlet. The partition wall and the surrounding wall together define an upper accommodating space and a lower accommodating space, which are communicated by a central perforation. The fluid outlet is at least communicated with the upper accommodating space. The handle is connected to the surrounding wall and has a passage communicating with the fluid outlet. The mirror unit is detachable and rotationally provided on the base, and comprises a mirror body and a rotating shaft. The mirror body is located in the upper accommodating space. The rotating shaft is connected to the mirror body and penetrates through the central perforation, and is connected with the driving module. Further, the rotating shaft is operable to be driven by the driving module to spin around the self axis and rotate together with the mirror body.一種口鏡裝置,包含一固持單元及一鏡子單元。固持單元包括一基座、一握柄及一驅動模組。基座具有一圍繞壁、一間隔壁及一流體出口。間隔壁與圍繞壁共同界定一上容置空間及一下容置空間且具有一中央穿孔以連通上容置空間及下容置空間。流體出口至少與上容置空間相連通。握柄連接於圍繞壁並具有一與流體出口相連通的通道。鏡子單元可拆裝且可旋轉地設於基座,並包括一鏡本體及一旋轉軸。鏡本體位於上容置空間中。旋轉軸連接鏡本體並穿設於中央穿孔且與驅動模組連接,並可操作地由驅動模組驅動而繞自軸旋轉且連動鏡本體旋轉。1‧‧‧固持單元11‧‧‧基座111‧‧‧圍繞壁112‧‧‧流體入口113‧‧‧流體出口113a‧‧‧上出口部113b‧‧‧下出口部114‧‧‧間隔壁114a‧‧‧中央穿孔115‧‧‧上容置空間116‧‧‧下容置空間12‧‧‧握柄121‧‧‧通道13‧‧‧驅動模組131‧‧‧軸承131a‧‧‧外圈131b‧‧‧內圈131c‧‧‧軸孔131d‧‧‧滾動件132‧‧‧槳葉133‧‧‧環形體14‧‧‧底蓋15‧‧‧導流部2‧‧‧鏡子單元21‧‧‧鏡本體211‧‧‧鏡面22‧‧‧旋轉軸23‧‧‧間隙3‧‧‧固定件
