PROBLEM TO BE SOLVED: To provide a drug solution administration device capable of suppressing deterioration of sealing performance of a seal member when a penetrating member is penetrated through a seal member arranged at an administration port portion. A drug solution administration device (10) includes a first housing (200) including a drug solution storage unit (221) capable of storing a drug solution and a casing (210) in which the drug solution storage unit is arranged, and a first housing (200) for delivering the drug solution into a living body. A second housing 300 configured to be connectable and separable from the first housing, the liquid supply section 440 in which the flow path 440a is formed, and the administration port section 400 in which the seal member 460 is arranged. The first housing includes a penetrating member 225 that communicates with the first flow path of the liquid solution storage unit and the liquid sending unit by penetrating the seal member as the first housing and the second housing are connected. Has a first convex portion 461 protruding toward the side opposite to the direction in which the penetrating member penetrates the seal member. [Selection diagram] Figure 4【課題】投与ポート部に配置されたシール部材に貫通部材を貫通させた状態において、シール部材のシール性が低下することを抑制できる薬液投与装置を提供する。【解決手段】薬液投与装置１０は、薬液を貯蔵可能な薬液貯蔵部２２１及び薬液貯蔵部が配置される筐体２１０を備える第１ハウジング２００と、薬液を生体内へ送液するための第１流路４４０ａが形成された送液部４４０及びシール部材４６０が配置された投与ポート部４００を備え、第１ハウジングと接続分離可能に構成された第２ハウジング３００と、を有しており、第１ハウジングは、第１ハウジングと第２ハウジングとの接続に伴ってシール部材を貫通することにより薬液貯蔵部と送液部の第１流路とを連通させる貫通部材２２５を備えており、シール部材は、貫通部材がシール部材を貫通する方向と反対側に向けて突出した第１凸部４６１を有している。【選択図】図４
