To provide a medical solution injection device of a new structure capable of preventing re-exposure of a hollow needle.SOLUTION: There is provided a medical solution injection device 10 in which a chemical solution stored in an interior reservoir 20 is poured out through a hollow needle 12 by a pushing operation of a pusher member 18 from a base end side to a device body 14 equipped with the hollow needle 12 at the tip side, and a needle tip cover 16 for protecting a needle tip 22 of the hollow needle 12 is assembled movably in an axial direction with respect to the device body 14. A positioning mechanism 116 for positing the pusher member 18 at a pushing position to the device body 14 is provided between the pusher member 18 that is pushed directly and the device body 14. Movement of the needle tip cover 16 to the base end side is regulated by a contact action on the pusher member 18 positioned at the pushing position by the positioning mechanism 116.SELECTED DRAWING: Figure 2【課題】中空針の再露出を防止することができる、新規な構造の薬液注入装置を提供する。【解決手段】先端側に中空針１２を備えた装置本体１４に対して基端側から押し子部材１８を押込操作することで内部リザーバ２０に貯留された薬液が中空針１２を通じて注出されると共に、中空針１２の針先２２を保護する針先カバー１６が装置本体１４に対して軸方向で移動可能に組み付けられた薬液注入装置１０において、押し子部材１８を装置本体１４への押込位置へ位置決めする位置決め機構１１６が直接押込操作される押し子部材１８と装置本体１４との間に設けられており、位置決め機構１１６で押込位置へ位置決めされた押し子部材１８への当接作用によって、針先カバー１６の基端側への移動が規制される。【選択図】図２
